Susan D. Snell is a fictional character created by American author Stephen King in his first published 1974 horror novel, Carrie.

After tormenting Carrie White in the locker room, Sue begins to feel remorse for her actions.

In the novel, King uses commentaries by Sue Snell as one of his innovative narrative techniques to tell Carrie's history.

When Carrie breaks down emotionally after having her first period in the shower, unaware of what menstruation is, Sue joins her classmates in gleefully taunting her and pelting her with tampons, repeatedly chanting, "Plug it up!"

Staying home on prom night, she begins to doubt her own motives: worry about her late period – she both fears and hopes she is pregnant – and the possibility of Tommy falling for Carrie.

When the town whistle begins blowing, Sue looks out her window, sees the fire at the school and rushes to her mother's car.

The deputy later recalls Sue stating "They've hurt Carrie for the last time", indicating that she had no part in what happened.

Three hours later, Sue finds Carrie lying by a wrecked car driven by Billy Nolan and Chris Hargensen, near death from being stabbed by her mother Margaret.

As Sue flees the scene, her period begins, insinuating that the trauma of the night has caused her to miscarry and that she is not pregnant.

In 1986, she publishes a book, My Name is Susan Snell, which details the events of the prom from her perspective, reminding readers that "we were kids" and apt to make faulty choices even while trying to do right.

However, feeling guilty about it, she eventually asks her boyfriend, Tommy Ross (William Katt), to take Carrie to the prom.

Unlike the novel, Sue doesn’t seem to feel worried over the possibilities of Tommy falling in love with Carrie.

Sue then notices the cord running along the stage, leading up to the bucket of pig blood above Carrie.

When Sue investigates the inside of the stage, she catches Chris briefly, but is forced out of the auditorium by Miss Collins (Betty Buckley) (who erroneously believes her to be interrupting the ceremony out of jealousy and does not listen to her protestations), seconds before the cord is pulled and Carrie is splattered with the blood.

Her mother did not let her attend any of the funerals and is seen talking to a friend about the aftermath, saying the family will leave town to avoid the media circus.

In the 1999 film The Rage: Carrie 2, set over twenty years later, Snell (again portrayed by Irving) is a guidance counselor at the new high school.

She closes off the mansion doors and launches a fire poker at a boy, unaware that Sue and Barbara are trying to get inside.

Carrie is able to sense that Sue is pregnant with a girl and saves her life by telekinetically sending her out of the house.