Dorian Tyrell was a mobster and one of America's professional killers, who worked for Niko, the Mafia chieftain of Edge City.
Tyrell's job was to oversee the management of Niko's casino, the Coco Bongo. However, Tyrell grew weary of taking orders from Niko, and with a number of henchmen loyal to him, planned to eliminate Niko in order to ascend to Don of Edge City.
Carrying out his sinister plot step-by-step, Dorian had his mole, Tina Carlyle, go to the local bank and use her handbag as a camera so that Tyrell, who was on the top floor of the Coco Bongo, could get a view of the bank's security system. Tyrell then organized for his right-hand man and best friend, Freeze, to rob the bank in order to obtain the cash necessary for their plot against Niko.
However, Niko's henchmen eventually discovered Tyrell's schemes. His criminal activities attracted unwanted attention from the police and the Coco Bongo was almost closed down by them due to their investigations. Unable to tolerate Tyrell's behaviour, Niko ordered his thugs to take Tyrell to meet with him. Niko threatened Tyrell via his thugs forcing him down at gunpoint, placing a golf tee in his mouth with a golf ball on top. Niko swung his club and hit the ball, giving Tyrell a bloody lip and narrowly avoiding his skull. After explaining that he would not tolerate Tyrell's plans, Niko informed Tyrell that he would not kill him if he left Edge City within a week.
Refusing to obey Niko's demand, Tyrell sent his most trusted henchmen (Freeze, Sweet Eddy, Murray, and one nameless henchman) to rob the local bank they had previously examined. Tyrell remained at the Coco Bongo to attend to his necessary duties along with his other trusted henchman, Orlando. But later that night, Tyrell's men returned with a mortally wounded Freeze, shot several times in the stomach, much to Tyrell's regret. Freeze informed Tyrell that someone robbed the bank before them and set off the burglar alarm, luring the police to the bank and resulting in a gunfight. Tyrell offered Freeze a cigarette, but when he was in the process of lighting it, Freeze died.
Enraged that the robbery attempt was a disaster and at losing one of his most trusted henchmen, Tyrell violently questioned Eddy as to who was the one responsible, and the terrified Eddy pointed to a green-faced, smartly dressed man below on the dancefloor. The man was Stanley Ipkiss under the influence of the mask, who was performing an intense dance with Tina. Tyrell and Orlando confronted Ipkiss and Orlando fired a single shot at him, which narrowly missed. Tyrell's henchmen threatened all the guests, who were ordered to leave. Tyrell and Orlando interrogated Ipkiss, who fooled around and didn't take their questions seriously. Unable to tolerate his wacky behavior, Tyrell ordered Orlando to open fire, but Ipkiss managed to flee. Shortly after, the police entered. Lt. Mitch Kellaway intervened and accused Tyrell of having his men rob the bank, as Tyrell's men were found on the scene. Tyrell and his men were then cuffed by Kellaway and taken to the police station, for fingerprinting and further questioning.
However, due to the fingerprints at the crime scene not matching those of Tyrell's men, Tyrell and his men were released. In an effort to exact revenge on Ipkiss, Tyrell placed a $50,000 bounty on his head.
Eventually, Tyrell and his men were led by Peggy Brandt to Ipkiss, who betrayed Ipkiss despite offering to help him hide from the police when he fled from them while under the influence of the powers from the mask. Tyrell gave the money to Peggy and took possession of the mask. He ordered his men to dangle Ipkiss over a Newspaper Printing Machine, despite Peggy's cries not to harm him. Tyrell demanded to know how the wooden mask worked. After being told by Ipkiss that he simply should wear it, Tyrell put on the mask, and dramatically transformed. His appearance differed significantly from the appearance of Ipkiss under the control of the mask. Rather than the thin and comical variant similar to Ipkiss, a bulkier and more intimidating version of himself was created, possessing an extremely deep voice, burning red eyes and purple, chapped lips, but still retaining the trademark green face. His hair was also the same even under the influence of the mask, contradicting Ipkiss, as his head under the influence of the mask was bald.
Tyrell then made a fake green mask and handed Ipkiss over to the police with it. The police drew the conclusion that Ipkiss was the culprit they had been looking for due to the presence of the mask with him. Ipkiss was then thrown into prison.
The next day, Tyrell heared that Tina had visited Ipkiss at the police station, and he and his men cornered her in the streets by gunpoint as she attempted to flee. As Tyrell threatened Tina not to betray him earlier, Tyrell then changed his rebellion plans, planning to kill Tina in the process.
That night, Tyrell, wearing the mask, barged into the Coco Bongo with his men. They confronted Niko and his gang, who were celebrating under the belief that Tyrell had left town. After a verbal confrontation, a gunfight took place. Two of Tyrell's henchmen were shot but his thugs succeeded in eliminating everyone except Niko himself. Tyrell challenged Niko to a shoot-out, prompting Niko to fire several shots at Tyrell, hitting him with all of the bullets but Tyrell was seemingly unharmed. He then proceeded to suck the bullets from his body and fire them back. Niko was hit several times and killed. Tyrell ordered his men to ransack the club, taking as much cash as they could. He then proceeded to use a bomb to destroy the Coco Bongo, taking Tina and many other innocent lives with it, unaware that Ipkiss had escaped from the police station and, aided by a reluctant Kellaway, was coming to find him for a final confrontation.
Ipkiss was captured by Orlando when attempting to sneak closer to Tyrell, after knocking out Bobby the Bouncer (who Dorian had used to block the back exit) and handing his gun to Charlie. Tina, tied to an artificial tree next to the bomb, tricked Tyrell into removing the mask for one last kiss. As Tyrell kissed her, Tina kicked the mask out of his hands, and a fight began, which involved Stanley's dog, Milo, managing to put the mask on. He then proceeded to attack Tyrell's men. Meanwhile, as the timer of the bomb continued to count down, Tyrell and Ipkiss fought until Ipkiss succeeded in knocking out Tyrell with solid punches.
Ipkiss retrieved the mask off Milo and put it on. He then managed to dispose of the bomb by swallowing it and freed Tina and also defeated Tyrell's thugs including Eddy, Orlando, Murray, and several nameless henchmen. Tyrell attempted to kill Ipkiss from behind with a penknife. But Ipkiss, using his powers, painted a flush handle on the tree, pulling it just as Tyrell entered the fountain next to them. The flush worked like a real one, and Tyrell, screaming, was flushed away into the sewers, followed by his penknife.
But one day, Dorian Tyrell was resurrected by Lord Zedd and Rita Repulsa, who gave him a mask of his own. Feeling grateful for the two monsters, he pledged himself to the villains and became one of their greatest assets. As time went by, Dorian met the Dazzlings and fell in love with Adagio Dazzle, and vice versa.
- Dorian will make his cameo appearance in the "Grim Grinning Ghosts" musical number in Lilo, Stitch & Twilight Sparkle's Adventures of Disneyland Fun along with the Dazzlings, Thrax, Lord Zedd, Rita Repulsa, Goldar, Scorpina, Rito Revolto, Squatt, Baboo, Finster, Prince Gasket and Princess Archerina.