Continuity mistake: The 6:00PM-7:00PM episode ends when it is still light outside. The 7:00PM-8:00PM episode begins when it is completely dark (no sunset/dusk/twilight) The show is supposed to be in "real-time" but as the sun goes down it gradually gets darker, it does not just become dark from one second to the next. Also, the California presidential primary takes place in June. It is not even close to dark at 7pm in June.
Continuity mistake: Emily Sloane's left ring finger was shipped to Arvin Sloane in one episode in Season 2, when they are reunited in the Philippines, the left ring finger is bandaged and missing. Later, in the episode when she is shot, when she tells Arvin the CIA is listening, the left ring finger is there.
Continuity mistake: When Flash plays tag with Faust ("Now you see me, now you don't"), there is a brief shot in which he rushes at Faust - but not inside Hyppolita's palace, but in some high-tech laboratory. Obviously a shot from some earlier series, since the coloring and style are different from the Justice League's.
The Catwalk - S2-E12
Continuity mistake: T'Pol says she has never been camping, but she went in "Strange New World."
Continuity mistake: When Aetius is about to leave Rome, he tells Valentinian he's going to Ravenna to take command of the 3rd Legion. The banners of this legion, however, have "LEG XX" on them, which means this is actually the 20th Legion.
XXXVII (The Birth of Evil Pt. 1) - S3-E1
Continuity mistake: Jack's father the emperor is a young man when he defeats Aku. At the conclusion of the movie, he greets his pregnant young wife. At the start of "The Beginning" movie, Jack is a very young boy, both his parents are well past middle age-and Jack has no sisters or brothers to explain the gap.
Crime of the New Century - S1-E9
Continuity mistake: In the fight scene at the start of the episode, Jesse knocks one of the GS agents into the water - in subsequent shots he has disappeared.