Michael has been portrayed by Chad Duell since April 20, 2010. Duell was nominated for three Daytime Emmy's for Outstanding Younger Actor in 2011, 2012, and 2014 and won his first Daytime Emmy for Outstanding Supporting Actor in 2015.
Starr was portrayed by Kristen Alderson on One Life To Live from 1998-2012 and on General Hospital from 2012-13. Alderson won her first Daytime Emmy for Outstanding Younger Actress in 2013 and was nominated for two more Daytime Emmy's for Outstanding Younger Actress in 2014 and 2015.
Starr moved to California to deal with an unknown issue with best friend Langston Wilde (OLTL former character) and this explains the required departure of the character due to Prospect Park's reboot.
Kristen played Kiki Jerome from 2013-15.
Michael is the son of the late, A.J. Quartermaine and his ex-wife, Carly Corinthos, and the adoptive son of mob boss, Sonny Corinthos. He is also the product of a one night stand between two people who hated each other.
Starr and her fiancé Cole Thornhart drive through Port Charles with their little girl, Hope, when they are hit by Anthony Zacchara's car. Both cars crash. Starr gets out, while Cole and Hope are stuck inside their car. Starr asks Anthony for help and he says that he can't because Sonny Corinthos is after him and that he has shot out his tires. Starr runs back to the car when Michael shows up and promises that he will save her family. After Michael can't do what he promises, he can't bring himself to tell Starr, who has been knocked out. Starr is devastated and is determined to make Sonny pay.
Later, Starr goes after Sonny with a gun and is about to shoot him when Michael shows up. Starr backs off Sonny and Michael turns her in to the police. Starr is sent to jail and her dad is not happy. Her dad, Todd Manning, makes a deal with Sonny that if Michael recants his statement to the police that he will keep his mouth shut about Sonny's girlfriend, Kate Howard, being responsible for shooting out Anthony's tires, which is information Todd overheard. Michael recants, and Starr is released from jail.
On the Fourth of July, Michael takes Starr to the Quartermaine's and, while they watch the fireworks, they kiss and decide to try dating to see how it goes. Michael's mom, Carly Jacks, and Starr's mom, Blair Cramer, are fine with the two dating; but the dads aren't. Todd is skeptical about it, and Sonny doesn't like the idea at all because of the fact that Starr pulled a gun on him. Kate tells Sonny that she thinks it's great and then Sonny sees the bright side.
During the Halloween week, Starr and Michael start making out on Starr's apartment couch. They end up dressing up and attending the Haunted Star's Halloween Party. Starr decides that she is ready to speed up the relationship. Starr heads back to her apartment, while Michael goes to the drugstore. Starr helps Michael deal with the arrival of the precieved died Michael's father A.J. and death of his great-grandfather Edward.
December 7, they try to have sex but this attempt is failed due to Carly knocking. Carly is there to apologize, but later gets into an argument over Michael wanting to work with AJ.
December 26 (Christmas episode with the setting as the 24th), Michael and Starr try to figure out which place to go to. Starr doesn't want to go to her father's and Michael is debating on which father he wants to go to (either to the Quartermaine's, with his biological father, AJ or to Sonny's, his adoptive father). Starr says that they can stay at the apartment and they end up having sex.
Starr and Michael have sex on February 5. Starr helps Michael and AJ in trying to figure out the secret ingredient of the pickle ralish. Starr helps Ellie Trout in examining the ralish. In middle of March, Starr gets a call from Langston Wilde, friend and adoptive daughter of Starr's great-aunt from OLTL, calls from Los Angeles. Starr states to Michael that she must leave Port Charles and Michael needs to stay to help AJ with the ELQ stuff. Michael is able to convince Starr to accept a ride on her father's private jet. On April 8, Michael is talking to Starr on the phone and Starr says that they are breaking up because she is staying in LA.Later on, after the horrible breakup, Michael has an off-screen connection with Brenda Barrett at Metro Court Bar. Michael is heartbroken and drank a bit, while Brenda was sad that Jasper Jacks wasn't marrying her due to Carly Jacks. Brenda drank as well, and they ended spending the night together over grief. It is later revealed after Brenda plays a few mind games, that Michael and Brenda never actually slept together.
- Michael was originally this age, but his birth year was later changed to c1992, which would have made him about 20 when he first started dating Starr.
- Starr was originally this age, but her birth year was later changed to c1991, which would have made her about 21 when she first started dating Michael.