Larry came to Port Charles with his wife, Arielle Gastineau Ashton. They came in on their yacht the Aphrodite, which broke down coming into Port Charles. He met Colton at the marine shop when they arrived and deeply in debt. His son Ned Ashton didn't want anything to do with him.
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 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.
Larry returned on October 27, 2014, inside of a sack left outside on the deck of the Quartermaine mansion. Tracy, Ned and Lulu Spencer-Falconeri 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 III, 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 showed up in Port Charles and is seen with his son, Ned and his ex wife, Tracy.
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]
Health and Vitals
Stuffed in a bag by Jerry Jacks and left behind outside the Quartermaine Mansion [Oct 27, 2014]
Nearly got hit in the head with a fire poker (fireplace poker) by Tracy Quartermaine [May 1, 2017]