Will Darnell is a character from Christine.
Novel
Will Darnell is the owner and manager of Darnell's Do-It-Yourself Garage, the garage that Arnie Cunningham takes his car, Christine, to just after buying it, with the intention of restoring it.
When he arrives, he is immediately harassed by Will, who yells at him for driving the car in while it blows noxious exhaust and the engine rattles loudly. Will dismisses Arnie as a worthless teenager, berating him and laying out the rules of the shop. Darnell says his business caters to men who are dependent on their vehicles for work "in order to put bread on the table", not for teenagers to go drag racing or joyriding. Arnie leaves, embarassed and humiliated, but returns to work on his car. He intervenes in a fight that breaks out between Arnie and Buddy Repperton only when it looks like Arnie is winning the fight.
Will comes to respect Arnie and puts him to work, cleaning up around the shop and stripping cars in the junkyard behind his place for parts. Admiring Arnie for his technical skill, Will eventually has Arnie making runs to Albany, NY to his largest parts supplier. It is revealed later in the story that Will also has Arnie first running cigarettes illegally across state lines, then hard drugs.
Like most people who come into contact with Arnie and Christine, Will has his suspicions about the car and knows something of its history and that of Roland LeBay. Due to Darnell's abandonment of Arnie when Arnie is arrested for smuggling cigarettes over the New York state border, Christine seeks revenge. On a cold winter's night, she smashes through the bay window of Darnell's home and tries to run him down. She doesn't kill him outright; Darnell himself, already in poor health, dies of a heart attack.
Darnell himself is described as a fat, cantankerous man who smokes and chews Roi-Tan cigars and is in generally poor health. His office is filthy and he often holds court, inviting his friends to smoke (despite signs all around the shop prohibiting smoking) and play cars after hours. Darnell also has his hands in nefarious, illegal businesses and may have been involved with the local mob. Dennis Guilder's own father worked for a short period of time as Darnell's accountant, but left Darnell's service when he found out about Darnell's illegal dealings. Surprisingly, Dennis' father left on amiable terms with Darnell.
Film
In the film adaptation, Will Darnell is played by actor Robert Prosky.