Sheridan is the much younger sister of Julian Crane, born when he was a teenager. She has always felt much closer to his son, Ethan, who is only a couple of years younger than she is. Her life was forever changed when she was an adolescent, first with the death of her mother, and then with her memory of finding a body (possibly a (Lopez) Fitzgerald, possibly killed by her) shortly after. Her family has always allowed her to believe she killed someone that night for reasons that have not yet been explained. She was sent off to spend years in a Paris mental institute, and later in her life, became friends with the late Lady Diana, the former Princess of Wales.

Sheridan returned to Harmony after being betrayed by her fiance Jean Luc, who wanted her only for her money (like so many others before him). She hasn't done much with her life up until now, always buying her way out of her problems. She couldn't do that when she crashed into Luis Lopez Fitzgerald's police car, and was sentenced to do 100 hours of community service at the Harmony Youthe Center. During that time, she flirted with and dated Hank Bennett, but it was Luis she fell in love with. It began in earnest when she followed him to New Mexico, hoping to prove Martin Fitzgerald was still alive, and was a certainty when Luis saved her instead of the man he thought was his father. (Turned out to be an imposter hired by the Crane family.)

Overhearing (yet another) imposter hired by the Crane family to "be" Luis claim he was using her, she decided, once her 100 hours was up (it took her nine months), to return to Paris. Unfortunately, in Paris, Roger and Pierre (the two most inept hitmen in history) are waiting for her. Luis followed her to Paris, and has saved her life more than once, but she still refused to return to Harmony with him. In desperation, he kidnapped her so he could get her safely back to the States. She had him charged with kidnapping, which almost resulted in the loss of his badge.

She continued to date Hank Bennett once back in Harmony, while still lusting for Luis. When it looked like the drug cartel followed her back to Harmony, the FBI assigned Luis to guard her (didn't really give him a choice). The two got closer and closer, even though Sheridan's dating Warren was a slight problem for them. Luis scared Warren off, leaving Sheridan alternately loving and hating Luis. Finally, in desperation, Sheridan went to Eve to hypnotize her about the night she found 'the body'. Her hypnotism seems to have revealed that she killed Martin Fitzgerald, but Eve convinced her that she was merely guilty about her mother dying at the same time, and associated the two events.

With this out of the way, Luis and Sheridan were finally free to be together...only the drug cartel, his hatred of her family, her family's hatred of his family, and her dating his best friend could have kept them apart. Despite all of that, the two finally admitted their love for each other, but before they could make love, Sheridan was shot and killed, leaving Luis heart-broken. But wait! It turns out she's not dead after all, and it was a plot by the FBI to make the drug cartel THINK she was dead. The only problem is that everyone who knows about the plan is being held hostage by the drug cartel, and she's in the casket!

Luckily Sheridan was saved from certain doom, and her and Luis finally got together. Unfortunately, their repeated attempts to become lovers have all been thwarted, the most recent by the revelation that Ethan is not a Crane. They finally managed to make it to the bedroom...and now they're headed to the altar! Luis has just become the latest in Sheridan's long line of fiancs.

Sheridan is currently believed to be dead after being missing in a boat explosion orchestrated by Julian and Alistair. Unbeknownest to her family, she is alive and well, being cared for by a fisherman named Brian O'Leary, and his friends, Liz and Doc. She believes her name to be 'Diana'.