As a little girl, Rose Canton would blame an imaginary friend for anything she herself did wrong. Rose's imaginary scapegoat became so real to her as she grew older that one day she believed she saw her "other self" the Thorn, in a mirror. To escape from her "Thorn" persona, Rose went to assist the famed botanist Professor Hollis in his research on the island of Tashmi. There Rose discoverd a jungle root whose sap gave her superhuman powers. The blonde rose physically transformed into the evil red-haired Thorn, who murdered Hollis. Rose could neither prevent herself becoming the Thorn nor could she control the Thorn's actions.

The Thorn became a professional thief and battled the original Flash (Jay Garrick). Rose told the Flash that the Thorn was her sister but he eventually realised the truth. Wonder Woman had the original Green Lantern (Alan Scott) take Rose to the Amazon island of Transformation to be cured of her split personality. Rose fell in love with Green Lantern and discovered his secret identity.

After it appeared she was cured, Rose returned to America where she assumed a new identity, Alyx Florin, and married Scott, who did not know who she really was. But on their honeymoon, Rose tried on Green Lantern's mystical ring and again became the Thorn. Rose managed to restrain her Thorn self from killing Scott. She threw the ring into the fireplace causing the cabin to erupt in flames. Rose fled, and Scott believed her dead. She later gave birth to their twin children, but Rose left them to be adopted and never returned to Scott, fearing that Thorn might kill them.

The Thorn persona took over, but eventually Rose's self resumed control. She later met her children, Jennie-lynn Hayden (Jade) and Todd Rice (Obsidian). Finally, when her Thorn self was about to kill Green Lantern and her children, Rose's persona forced the Thorn to stab herself fatally. She died as Rose, and the Harlequin revealed to Scott, Jade and Obsidian what the Rose's true relationship to them was.

Rose Forrest

Rose Forrest is the daughter of police Detective Sergeant Phil Forrest. One night Forrest and his partner Danny Stone were hunting down the 100, a powerful Metropolis-based criminal organisation, when they became involved in a gunfight with some hoods belonging to that group. Stone was wounded - not fatally- but enough to take him temporarily out of action, and Forrest pursued the fleeing villains on his own. Their car chase ended down at the waterfront, when Forrest rammed his car into the car of the criminals. However, the 100 had offered the hoods a bounty for the head of Forrest, and they killed him, dumping him and his car into the river.

The next morning Rose and Danny Stone arrived at the scene just as the car containing the corpse of Phil Forrest was being pulled from the waters. Distraught terribly, Rose was hospitalised through her trauma. She developed a split personality as a result of her obsession with avenging her father's death. Incapable of violent action as Rose, while asleep, she would sleepwalk in her new, vengeful personality.

Rose continued to live in the home she and her father had shared. Sleepwalking one night she went through a secret door that she had discovered years ago as a child and entered an abandoned costume shop. There she found a costume and weapons created years ago by a costumer named Albert Talbot as part of his aborted scheme to turn a woman he knew into a costumed criminal. Donning an Auburn wig, and taking the costume and weapons, Rose became the Thorn, whose primary motivation was to avenge her father's death by battling the 100.

Thorn clashed regularly with the 100 but later dropped out of sight for sometime. She reappeared in her Rose persona as creative director at McClellan and Johnson, an advertising agency that worked with Booster Gold at the launch of his career.

Rose's relationship with Danny Stone appears to have petered out, and she never knew that she was the Thorn. Whilst the Thorn, she had no idea of her Rose identity either.