The Dark Phoenix (2): The Inner Circle - S3-E12
Continuity mistake: When Cyclops blasts a hole in the floor beneath Sebastian Shaw and causes him to fall through it, Shaw lands on a catering table. Later when Beast jumps down the hole to attack Shaw, Shaw is emerging from underneath heavy rubble rather than a catering table, and he is inexplicably shirtless. The rubble also changes from being brown just before Beast jumps down the hole, and is then white after he lands. Additionally, the floor goes from being black-and-white checkered to a solid brown color. (00:15:55 - 00:17:05)