Jess invites Paul, a music teacher from her school that she's always had a crush on, to the gang's big Thanksgiving dinner, which naturally goes horribly awry.
Cheryl and Dana find themselves locked in the garage having ignored Jim's advice on how to open the garage door from the inside.
Lupo and Bernard discover that two scientists who were found dead in a fire were stabbed beforehand. The investigation soon leads to a mentally disturbed woman.
Zach dumps the girl he's dating when she obsessively sends him text messages and goes to Billie to seek relationship advice. Davis also asks Billie's dating advice.