Revealing mistake: Bad guy is shot but can be seen breathing afterwards on the ground. At the start of the next episode, he was shown to be shot in the head. (00:40:38)
Continuity mistake: The clock just tells the viewer that it is 4:40am. Sen. Palmer interrogates his son about the rape of his daughter. In the room, there is a clock that shows 4:57am instead. (00:27:43)
Day 5: 1:00 AM - 2:00 AM - S5-E19
Factual error: When Chloe is at Bill's, she brings up the details of the diplomatic flight, and it shows the aircraft as a Boeing 757-200. This is a twin-engine aircraft, but the one shown is a tri-jet.
12:00 Midnight-1:00 A.M. - S1-E1
Continuity mistake: Kim Bauer has a full set of glittery pink disco nails on episode one (midnight) but then these are not visible at all in most episodes. In the 2pm episode her nails look clean/natural in nearly all the shots, apart from during the phone call with Rick where traces of pink glitter can be seen. I know she's had a very rough night but it doesn't explain the amount of damage her nails have sustained.