Hugo Napier portrayed the character from October 9, 1988 to 1989 and from 1991 to 1992.
On September 22, 2014, it was revealed that Napier would return to GH to reprise the role of Larry. Napier returned from October 27 to December 1, 2014. He also made an appearance on January 25, 2016.
In 2017, the role was recast with Oliver Muirhead, who held the role from March 23 to May 1, 2017.
They were in search of the Dragon Bone, a key to unlock an ancient Chinese Civilization. Tracy Quartermaine blackmailed Larry into giving her and Ned Quartermaine a share of the treasure if he found it. Tracy said she would expose him as not being the Ashton family heir if he did not.
The search ended when Robert Scorpio's dog Friday buried the key. Larry and his wife left Port Charles. He lost his title when Charlie Prince turned out to be the real heir. Larry returned to Port Charles in 1991. He formed a cartel to control global business with carbon disulphide. To achieve their goals, they thought it would be best for Paul Hornsby to marry Tracy to take over her stock of ELQ. Killing her was an option to get control of her stock. The cartel was discovered and put to an end by the Port Charles Police Department.
On October 27, 2014, Larry returned to Port Charles inside of a sack left outside on the deck of the Quartermaine mansion. Tracy, Ned and Lulu Spencer rush outside thinking Luke Spencer is inside the sack, but when they open it, a disoriented Larry emerges. Larry seems a little drunk and is just as confused about his whereabouts as Tracy, Ned and Lulu are. Tracy made a deal with Jerry Jacks, where she gave him ELQ stock in exchange for the release of her husband, Luke, whom Jerry claimed he was holding hostage. Instead of giving Tracy, Luke, he gave her Larry, because he never specified which husband he would return to Tracy in exchange for ELQ stock.
Larry stumbled around the mansion drunk, but it was all a ruse. Larry is working with Jerry and Fluke. He tried to persuade Tracy and Ned to usurp Michael Corinthos, so Tracy could take control of ELQ. Soon after, Michael arrived at the mansion and announced that he was officially changing his name to Michael Quartermaine. Larry was indignant at how rude Michael was to him and was disappointed that Ned didn't defend him. Later, Patrick Drake and Sam McCall overheard Larry talking with Jerry on the phone. They realized that Larry is working with Jerry.
Patrick and Sam broke into Larry's safety deposit box and discovered a photo of Cesar Faison and a flash drive containing plans to make a high tech WSB mask. Larry was stunned when Alexis Davis walked into the Quartermaine mansion with the real Luke Spencer. However, the real Luke is being held captive elsewhere and Fluke is pretending to be the saved one. On December 1, Larry fled town in order to evade the police.
On January 25, 2016, Larry showed up in Mexico where Tracy is staying.
On March 23, 2017, Larry returned to Port Charles and was seen with his son, Ned and his ex wife, Tracy.
On April 26, 2021, Brook Lynn calls her grandfather Larry to ask about acquiring a baby as she is faking a pregnancy. He tries to sell her bitcoins which she turns down and the call is interrupted by Olivia and Dante coming into the room as Brook Lynn yells at Larry that she is asking for his help.
Helped form a cartel in order to control global business using lethal carbon disulfide 
Falsely posed as the Ashton family heir 
Fled town in order to evade the police [Dec 1, 2014]
Hired Samira Adin to pretend to be Edward's daughter so she could con Tracy out of her painting [Apr 2017]