Lindstrom also portrays Ryan's identical twin brother, Kevin Collins on GH.
While portraying Kevin, Lindstrom reprised the role of Ryan from August 10, 2018 until the character's presumed death on March 8, 2019. Lindstrom reprised the role again on May 22, 2019 and has been pulling double duty by playing both Ryan and Kevin in a recurring capacity since then.
Dr. Ryan Chamberlain was a pediatrician at General Hospital, but it was revealed that Ryan hid his mentally unstable behavior for quite some time.
He has an identical twin brother named Kevin Collins, who is a psychiatrist and a trusted and valued member of society.
Ryan was presumed dead in a fun house explosion on March 24, 1995.
It was revealed that Ryan was sexually abused by his mother, Melanie Chamberlain. One night, Melanie abused Kevin, thinking he was Ryan. Kevin told their father, Victor Collins, who took Kevin away and left Ryan behind.
On August 10, 2018, Ryan was revealed to be alive and was being treated by Kevin in Ferncliff. Kevin was contacted by the DVX in May 2018 and they said that they had an operative who was suffering from deep psychosis. They were going to have him killed unless Kevin took him off their hands. Kevin was shocked to learn that the operative was Ryan, his twin brother.
On August 28, 2018, Ryan got the upper hand and knocked Kevin out, before he switched clothes and places with him. Kevin was being held captive in Ferncliff while Ryan began to impersonate Kevin on the outside.
During Ryan's reign of terror in Port Charles, he killed Mary Pat Ingles, Kiki Jerome, and Peyton Mills. He also stabbed Lulu Spencer but suddenly went blind before he could finish her off. Lulu survived, but she didn't remember who attacked her, so Ryan (after having his sight restored) was going to "help" her remember what happened, but he tricked her into naming Franco Baldwin as her attacker.
In March 2019, Ryan was finally exposed as the killer after Franco revealed this news to Jordan Ashford, who had previously ordered Franco to plead guilty in an attempt to draw out the real killer. On March 4, Ryan and Ava went to Niagra Falls and they planned to go to Canada and start a new life together as husband and wife, but Jason Morgan and Laura Collins later caught up with them as they were headed towards the border on foot by crossing a footbridge. After Jason shot Ryan in the back of the shoulder, Laura revealed to Ava that her fiancee was not Kevin; he was actually his twin, Ryan Chamberlain. After Ryan kissed her and threw himself and her off the footbridge, Jason saved her while Ryan fell into the river and was presumed dead. Laura explained to Ava how Ryan had impersonated Kevin for months, and that she was with Ryan all this time. Ava was emotionally destroyed when she learned that it was Ryan who killed Kiki and that she was involved with a serial killer all this time.
On April 5, it was revealed that they found Ryan's right hand which had somehow been severed from his body. On April 19, Ryan had mailed Kevin his right hand.
On April 29, Ava, Franco, Kevin, Laura, Mac and Felicia Scorpio, and Lulu Spencer had a memorial service for Ryan, but it was only to help draw Ryan out of hiding. Kevin and Ava had to pretend to be a couple to lure Ryan back to Port Charles since Ava is the object of Ryan's obsession.
On May 14, it was revealed that Ryan is indeed alive and that Nurse April Tremblay was hiding him. When April was alone, she called Laura and Curtis Ashford back to her cabin, but Ryan killed April before they got there. Ryan knocked out Curtis before he went to attack Laura, who was terrified. Ryan tied Laura and Curtis up back to back and rigged the cabin to explode, but they made it out before the cabin did explode.
During the 2019 Nurse's Ball, Ryan returned to Port Charles and knocked out Kevin backstage before putting him in a straightjacket and hanging him over the stage. Ryan stalked Ava and knocked out Scott Baldwin backstage when he figured out the truth. Ryan followed Ava to a cabin and revealed himself to her, even pulling out a knife to threaten her with. It took some work, but Ava convinced Ryan she still loved him and wanted to run away with him. When he put the knife down, Ava pulled out her gun and confronted him over Kiki's death and revealed she was planning to kill him since the moment she found out he killed Kiki. Ryan didn't believe she was going to kill him, and insisted that she loves him. Ava was about to kill him, but Curtis showed up and stopped her since Ryan could be a kidney donor for Jordan Ashford. Ryan was arrested, but Ava literally stabbed him in the back after he taunted her about loving him.
Through her father, she has four half-siblings; Olivia Jerome, Julian Jerome, Evan Jerome Sr, and the late Dino Antoinelli. Through her mother, she had a half-brother named Johnno Ryan, who is deceased.
She is the owner of the Jerome Art Gallery and is a former mobster working in the Jerome mob family.
Her daughter Kiki was killed by Ryan Chamberlain on Thanksgiving Day in 2018.
From November 21, 2018 until March 8, 2019, Ava began dating Ryan, thinking he was his twin brother, Kevin Collins. In February, "Kevin" proposed to Ava and she said yes. In March, they planned to elope in Canada and start new lives together, but Jason Morgan and Laura Collins stopped them and revealed to Ava that her fiancee was not Kevin, he was Ryan. To evade police capture, Ryan threw himself and Ava off the footbridge, but Jason saved Ava as Ryan fell to his presumed death.
On September 4, after Kevin paid Ryan a visit, Ryan managed to get the upper hand and he knocked Kevin out before he switched clothes and places with him. While Kevin was stuck in Ferncliff, Ryan was on the outside and began to impersonate his twin brother.
On September 28, Ryan officially met Ava Jerome after he mistook her for Felicia Scorpio. Afterwards, Felicia approached Ryan (thinking he was Kevin) and insisted that they had so much to catch up on.
On October 4, Ava went to see Ryan (thinking he was Kevin) and became his patient. Ava shared her feelings with him about how she was betrayed by her daughter, Kiki Jerome and her ex, Griffin Munro before saying she felt nothing but rage. She told Ryan that she wanted Griffin and Kiki to hate her as much as she said she hated them.
On Halloween, Ryan murdered Ferncliff nurse Mary Pat Ingles by stabbing her to death and placed her decapitated head into an apple bobbing barrel for Carly to find. The rest of the corpse was placed in Ava's art gallery with a jack o lantern as its head. Ryan (as Kevin) also separated from Laura, the woman the real Kevin is married to. On November 21, Ryan finds Ava and Nina fighting in Ava's art gallery and breaks it up. He then tells Ava that he has feelings for her and they kiss and Laura walks in and sees them kissing.
On November 26, Ryan murdered Ava's daughter, Kiki Jerome by stabbing her to death in her apartment and then placed her corpse inside the Haunted Star, where it was found by newlyweds Curtis and Jordan Ashford. Ryan also hid the murder weapon in the apartment of Kiki's boyfriend, Dr. Griffin Munro, who is subsequently arrested after the knife is uncovered. However, Griffin is soon released as the PCPD suspects that the same person killed both Kiki and Mary Pat. Meanwhile, Ryan had began sleeping with Ava since the day he murdered Kiki and even stopped Ava from killing Griffin at the PCPD.
On New Year's Eve, Ryan murdered film producer Peyton Mills, who was producing a documentary about him, and stashed his body in the balcony of the Metro Court before celebrating the new year with Ava.
On January 21, 2019, Ryan stabs Lulu Spencer-Falconeri in her office after she gets too close to figuring out that he is actually not Kevin. He does not kill her and she gets away due to him suddenly going blind. Lulu is rushed to GH and Ava takes Ryan there too where he is revealed to have been infected with the same virus which had rendered Anna Devane temporarily blind. After his sight is restored, Ryan tries to finish off Lulu in her hospital room, but had to leave when Laura came in. After Lulu says she wants to remember what happened, Ryan convinces Lulu to let him Hypnotize her so she can regain her memory of who tried to kill her. He manipulates her memory to believe that it was Franco stabbed her. Franco is subsequently arrested and charged by the PCPD for Lulu's stabbing and the triple murders.
On February 18, Laura discovers Kevin in his cell at Ferncliff, prompting Ryan to drug her from behind and trap her in the basement alongside Kevin, who is still blinded by the virus Ryan had been cured for. On February 20, after asserting his innocence for while, Franco surprisingly pleads guilty to all charges as part of Jordan's secret plan to flush out the real killer. An enraged Ryan then became engaged to Ava despite her doubts and confronted Franco at Ferncliff about why he pled guilty. Franco unwillingly reveals Jordan's plan to him, but Ryan tells him that Jordan is in critical condition after a car accident and then stabs him in the stomach. After revealing his true identity as Ryan the serial killer, Ryan prepared to finish Franco off and stage his death as a self-defensive act, but a nurse arrived and Ryan asked her to get help. As she left, Franco attacked Ryan and escaped the cell before shutting the door on Ryan. However, the nurse returned to free Ryan, who soon put Ferncliff under lock-down. Franco had already escaped the facility and told everyone that Ryan was alive and the killer before being treated for his wound.
On March 1, Ryan and Ava planned to get married and flee to Canada, a plan which was denounced by Mac, Felicia, and Carly. As Ryan went to the basement parking lot of GH to check on his box of drivers' licences in the trunk of his car, Carly appeared behind him, wanting to confront him about Ryan's alias, Todd Wilson, used to identify the patient she talked morse code with long ago (actually Ryan). Ryan knocked Carly unconscious and locked her in the trunk before Felicia confronted him about his engagement to Ava. Ryan shut down Felicia and then drove Ava to a cabin en route to Canada. Unbeknownst to him, Kevin and Laura had escaped from Ferncliff and the latter told everyone that Franco is right about Ryan being alive the killer.
On March 6, once they reached the motel, Ryan and Ava slept together again and showered, but while Ryan was showering, Ava went to look for her shoes in the car and accidentally discovered Carly in the trunk. After a brief encounter with Cameron Webber, Ryan appeared behind Ava and told her that the gagged up Carly was her wedding present, confusing her to the point that 'Kevin' is having another mental breakdown. Ryan later dumps Carly off at the bottom of a bridge and leaves her to die before returning to the motel and declaring to Ava that he's desperate to marry her.
Ryan and Ava leave the motel and rush over to a nearby crossing bridge leading to Canada, but Ava stops and demands Ryan to call 9-1-1 to ensure Carly's safety. However, Ryan forcefully persuades her into believing that they can run away into a world of paradise and as they leave, Jason Morgan arrives and shoots Ryan in the back of the shoulder before telling Ava to move out of the way. Laura arrives moments later and tries to tell Ava that her fiancee is not Kevin but Ryan and that the real Kevin is back at GH. Jason fires a warning shot and threatens to finish Ryan, who tells him that he will never know what happened to Carly if he kills him now. Meanwhile, Ava continues to believe that 'Kevin' is having another nervous breakdown and is told by Ryan to not believe Laura since she wants them to be separated. As police approach their location, Ryan grabs Ava, profoundly declares his love for her, and throws her and himself off the bridge. Jason is able to catch Ava while Ryan falls into the river below to his presumed death. Laura eventually tells Ava the whole truth, leaving her emotionally destroyed, and Jason rescues Carly.
On April 4, Ryan appeared in Ava's nightmare and the day after, Jordan said that the Canadian authorities have discovered Ryan's right hand, which Ryan might have severed off to make everyone believe he is dead. Ava does not believe that Ryan died, and Jordan also thinks this. On April 19, Kevin receives a package from Ryan and inside the package is Ryan's severed right hand.
On May 14, Laura and Curtis came to visit a nurse named April Tremblay in Toronto to ask about Ryan's whereabouts, but she told them nothing and the nurse told a figure (most likely Ryan) that they were gone and the figure stabbed an Invader article depicting the publicity of Kevin and Ava's 'romance' back in PC. On May 15, Ryan killed April after she told Curtis and Laura to come to her cabin quickly, and then ambushed the two when they discovered April's corpse. Ryan then tied Curtis and Laura up in chairs and left them to die in the cabin he rigged with explosives, but they were able to escape before it blew up. On May 21, Ryan returned to PC and knocked out Kevin backstage as Ava was performing at the Nurse's Ball. Ryan, pretending to be Kevin again, came across Scott while rushing to the stage and then knocked him out when Scott found out he's Ryan after he accidentally pulled off his fake hand. Ryan then left Kevin hanging from the roof of the stage for the guests to see and followed Ava to her new compound. Ryan pulls out a knife and Ava is able to convince him that she still loves him, and that Kevin could never replace what they had. She tells him that she wants to run away with him, and then after she gets him to put the knife down she pulls out her gun. Ryan says that she won't kill him, and she shoots the gun around him a few times. Ava and Ryan both don't know that Ryan needs to stay alive because his kidney is needed for Jordan who is in desparate need of one due to her accident. Curtis shows up right before Ava can finsh Ryan off he is able to convince Ava to put the gun down. Chase shows up and Curtis tells him to stand down. As Ryan is getting arrested he says to Ava "You couldn't pull the trigger; you love me." This infuriates Ava and she grabs his knife and stabs him in the back.
Ryan is brought to GH and is treated for his stab wound. He makes it out of surgery and he is also a match to donate his kidney to Jordan Ashford. At first, he tells Curtis to clear his name and not have him sent to prison, but that won't happen. Curtis tries to talk to him and that also doesn't work, but after someone (later revealed to be Dr. Finn) injects him with a substance which made him briefly convulse, Stella is able to convince him on June 4. He signs the forms after Finn tells him he will treated with equal care while under the knife and Stella tells him she will speak for him at his sentencing. On June 6, Ryan fell into a coma after he had the surgery to have his kidney removed.
On June 12, after being transferred to Pentonville, Ryan woke up and realized his kidney was stolen but his rant fell on deaf ears. It was eventually revealed that Kevin forged Ryan's signature and there was a conspiracy to steal Ryan's kidney and give it to Jordan. Eventually, Ryan met Nelle Benson, whom he bonded with over their hatred for Carly and the fact that they each got a kidney stolen from them. Before that, Ryan asked Nelle if he knew her from somewhere.
On July 19, Curtis and Jordan visited Ryan, who taunted them about having his kidney stolen but Curtis said that Ryan can't prove it. Curtis also told Jordan not to feel guilty about living.
On July 30, Ava visited Ryan and told him to let go of her for the sake of allowing Kiki's soul to rest, but Ryan does not regret killing Kiki and tells Ava that they are eternally bonded despite Ava saying that she only consented to be with Kevin not Ryan.
On October 8, Ava visited Ryan again and wanted him to stop writing to her, but Ryan kept insisting that Ava loves him and needs him just like he loves and needs her. Ryan also got jealous because Ava was seeing a new male therapist and mentioned that she's falling apart without him.
On October 17, Ryan was still looking at the picture of Ava on the cover of the crimson magazine she was on and his cellmate, Bryce Henderson called Ava "hot" and said he would have to look her up when he gets out of Pentonville. Ryan didn't take too kindly to that and stabbed Bryce to death with a pen. This caused Det. Chase to question Ryan about his latest act of violence despite Ryan trying to make Bryce's death appear like a suicide. Chase taunts Ryan (who his chained to his cot) about Ava, causing Ryan to lunge at him and being transported to another location.
On October 1, 2020, Ava received a collect call from Ryan, who wanted her to visit him in Pentonville and warned her her about there being dire consequences if she didn't come. Julian and Nikolas Cassadine pleaded with her, and after Julian left Wyndemere, Nikolas told her not to engage with Ryan. Ava compared Nikolas to Ryan at first, but apologized to him when she noticed he was genuinely concerned about her and the hold Ryan had over her. Ava acknowledge that Nikolas was nothing like Ryan despite everything he did to her in the past.
When Ava visited Ryan in Pentonville, Ryan revealed to her that Nelle Benson-Jerome left him a letter containing information about Julian's involvement in keeping Michael Corinthos' son Wiley from him. Ryan offered make sure the letter stayed with him and would not be sent to Sonny Corinthos if Ava visited him every week. Ava initially refused, but then agreed when Ryan threatened to turn the letter over to Sonny. He also wanted her to share her innermost thoughts during their weekly visits, and to not despise him. Nikolas showed up and was wanting to get Ava out of there, but Ava insisted that her discussion with Ryan had nothing to do with him. Eventually, after Nikolas agreed to give Ava another minute, Ryan decided that their visits would be meaningless if she remained married to someone else, so he ordered her to divorce Nikolas.
On October 13, Ava visited Ryan again and proposed a counter offer. Ryan was intrigued, and Ava revealed that she blackmailed Nikolas into marrying her because she wants his money. She told him that her marriage to Nikolas was loveless and told him about a postnup in her marriage that will activate if either one of them cheats on the other. If one spouse cheats, the other spouse inherits 90% of the Cassadine fortune. Ava promised Ryan a cut of the money and that he would make her happy. Ryan told her he had no use for the money since he is in Pentonville, and he turned her down because he felt there was a spark between her and Nikolas. Ryan claimed he didn't want to take Julian away from her, but he did stand by his original demands. Afterwards, Ryan hung up the phone and went back to his cell, leaving Ava perplexed.
On October 23, Ryan sent Julian an ominous post card, presumably to taunt him about having leverage over him.
On Halloween (shown on October 30), Ava paid Ryan another visit and claimed that she officially divorced Nikolas Cassadine. Ryan wanted proof, so Ava showed him the divorce papers. Ryan in turn had a guard give Ava the letter she wanted, but when she opened it, she was surprised to see that it said, "Do you think I'm stupid?" Ava tried to convince him they were real, but Ryan didn't buy it and said that he had a cellmate who was an expert in forgery before implying that he killed him. Ryan grew furious and screamed that every woman he loved has lied to him and that they were all alike, and he called Ava a traitor and vowed to make her pay as the guard had to drag Ryan away.
Ryan later called Sonny Corinthos and requested for him to pay him a visit in Pentonville.
- In 2013, it is stated that Dino had died in prison.