Chuck Versus the Gravitron - S2-E8
Revealing mistake: In the scene where Ellie is testing her Thanksgiving turkey by giving Morgan a piece, when she throws it in the trash he says 'no no no Sarah.. what are you doing!', which is the actor's name (Sarah Lancaster), not her character's. Maybe edited in some versions. (00:09:40)
Revealing mistake: A recycled shot from an earlier episode causes Bob to enter the room wearing one costume and then suddenly be wearing another when he turns to begin his scene with Dresden and co. (00:11:50)