He was portrayed by Gene Farber from September 21, 2017 to November 9, 2017.
After Ava Jerome's face was scarred in a fire, Valentin Cassadine told her about Dr. Klein, who had removed his birth defects years ago. Ava met Klein in St. Petersburg, Russia, when she checked into an upscale private clinic, the Boronsky Clinic. Klein agreed to help Ava, but she needed to keep away from Patient 6 who was sedated because he was dangerous. Ava ignored Klein and discovered that Patient 6 was a prisoner at the clinic.
Ava wanted her scars to be fixed so she tried to hide her visits to Patient 6 but Klein kept finding them together. He told her that he wouldn't treat her anymore if she kept ignoring him. Patient 6 gave Ava a piece of paper with a phone number on it. Klein took the number and called someone to explain that Patient 6 couldn't be controlled anymore with the strong tranquilizer he had been given. Klein was told to increase the dosage of the tranquilizer even if it meant an overdose.
Patient 6 fought off the new stronger tranquilizer and Ava helped him break out of the clinic. When Klein found out, he was furious and sent his henchmen, Greg and Anderson, after Patient 6. Klein wouldn't treat Ava anymore even though her first treatment was a success. He locked Ava in her room but she broke out and went back to Port Charles while Greg and Anderson tracked her down.
Klein knew that Patient 6 was Jason Morgan so he needed to find him. Since Klein and Andre Maddox worked for the same man, Klein asked Andre for his help. Andre had mind-mapped the memories of Jason and his identical twin Andrew Cain. Drew was implanted with Jason's memories which made him believe he was Jason. Andre was placed in Port Charles to keep an eye on Drew and make sure Drew didn't remember his own memories. Andre told Klein that Franco Baldwin was trying to figure out what happened to Drew, who was raised as a brother to Franco when they were children.
Klein gave Andre a fake death certificate for 'Andrew Moore' to stop Franco's search for the truth. Klein told Greg and Anderson to crash Sam McCall and Drew's Aurora Media launch party at the Metro Court. Klein wanted to draw out Jason by using Sam as bait. Klein also had another henchman, Delvin, drug and kidnap Sam and bring her to Klein, who was waiting at the pier. Jason shot Delvin which caused Klein to panic and toss Sam in the harbor before he ran off.
Valentin Cassadine wouldn't help Klein and even called the police to tell them Klein's location. After Klein was arrested, Sonny Corinthos paid his bail because Sonny wanted to know who Klein was working for. Andre had also been arrested and told the truth about the mind-mapping. Jason and Sonny wanted the truth from Klein but he didn't know who he worked for since they only spoke by phone.
Klein wanted to leave town before his boss found out he was helping Jason and Sonny. Sonny had his surveillance expert, Brick, trace a call between Klein and his boss but all Brick learned was that the caller was also in Port Charles. Sonny left Klein's fate in Jason's hands. Jason told Klein to put the formula for fixing Ava's scars on a flash drive and Klein did. Jason sent the flash drive to Ava and handed Klein back over to Sonny. Sonny told Klein he had no use for him and Klein could leave town.
- Worked with Dr. Boronsky to keep Jason Morgan/Patient 6 drugged and confined in the Boronsky Clinic in Russia for several years under the orders of Peter August [Oct 2012-Oct 2017; revealed on Sep 19, 2017; revealed to have been under Peter's orders on Jan 31, 2018]
- Tried to sedate Ava Jerome after he discovered she'd helped Jason Morgan/Patient 6 escape [Oct 3, 2017]
- Ordered his henchmen, Greg and Anderson, to apprehend Jason Morgan/Patient 6 [Oct 3, 2017]
- Imprisoned Ava at the Boronsky Clinic for helping Jason Morgan/Patient 6 [Oct 3, 2017]
- Set a trap for Jason Morgan/Patient 6 [Oct 24, 2017]
- Provided Andre Maddox with a falsified death certificate for Andrew Moore [Oct 26, 2017]
- Shoved Sam McCall, who was heavily sedated, into the harbor [Oct 27-30, 2017]
- Appealed to Valentin Cassadine for aid and money to get a new identification and flee the country [Oct 31, 2017]
- Skipped bail after arrest [Oct 31, 2017; went into hiding on Nov 9, 2017]
Health & Vitals
- Overpowered and injected with tranquilizer by Griffin Munro when Klein tried to inject Ava Jerome [Oct 3, 2017]