The Magician - S3-E4
Revealing mistake: When Oliver meets Thea at the Grind and Jot Cafe (Which looks unsurprisingly like CC Jitters) you can see the cups on the table are from CC Jitters. (00:20:50)
Revealing mistake: Early in the episode the dead body in the barn ever so briefly flutters his eyelids.
Revealing mistake: When Wan pets the cat deer for the first time, the animal pushes his head under Wan's arm. The horn then goes right through his shoulder. (00:17:55)
Revealing mistake: When the band in the nightclub performs the made up song "Mr. Music Man", the suave Mr. Stone, the musician Miss Fisher ends up dancing with, is doing one heck of an hilariously incompetent job at faking to play an instrument, basically playing air-banjo strumming about 3 inches above where the chords are, and wildly off tempo. In the closing bit of the song (as the singer sings "To sin") he even moves his hand at the side of the strings and not above them. (00:03:30)
Revealing mistake: It's a valiant effort, but the scenes of Sherlock & Irene in a London street are shot in New York. Not only is the architecture wrong but you can see a U.S. pedestrian crossing signal over Irene's shoulder. (00:16:15)
Revealing mistake: In the scene on the roof when Severide is removing the helicopter door with a spreader, there is no hydraulic pump or hoses attached, just the bare tool. When he sits the tool down you see this. So the spreader would not be working at all.
Revealing mistake: When Elliot and Maggie first arrive in Boston and Elliot begins reporting on the 31 injured patients, in several shots Maggie is supposedly on the phone with Jim back in New York. In each shot if you look closely you can see her iPhone's screen is lit up and is on the home screen, meaning she isn't actually on the phone.
Revealing mistake: In the scene at the beginning when Scarlett is signing autographs after hers and Gunnar's small concert, you can see her signing a poster with a marker that doesn't leave any ink on the poster. (00:08:15)