Shoveling coal

Medical students bully one of their own. And three years later, the mistreated person takes revenge in a cruel way. The students have a costume party on the train and, to everyone's horror, they're being stalked in this moving capsule with no escape route. Standard 80s horror slasher by Roger Spottiswoode, starring Jamie Lee Curtis, Ben Johnson and David Copperfield (his only action role in fictional movie).