Visible crew/equipment: After Reddington warns Liz of the Wendigo, he leaves, and the camera pans out. We see the entire set: Liz on the couch, the stage with the entire set, the theater seating, camera ladders, the lighting, etc. (00:04:40)
Suggested correction: This is a theatre used for plays, and it's Red's temporary safehouse for Liz. In the previous episode, The Djinn (No. 43), Red talks about this theatre owned by Gerta. Red says, "Her theatre is ours as long as we need it." So, Red and Liz are using it to hide out.
Revealing mistake: When Tom Keen is on the phone at the end of the episode, he is holding the phone backwards with the screen away from his ear. (00:41:20)