Hannah, Mack, Kerry and Lewis. Four friends enjoying Parker High School's cross-country train tour from Chicago to San Francisco—until they learn what is on the train with them... a coffin. Frog's coffin.

One by one, Hannah's friends guiltily confess all the nasty things they did to Frog before his sudden and horrible death, and then, one by one, they are viciously attacked.

It seems that Frog is out for revenge. But Frog is dead... isn't he?