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Day 4: 9:00 P.M.-10:00 P.M. - S4-E15

Continuity mistake: Chloe tells Michelle that she's confirmed Marwan's identity using voice tags from McLennan Forrester, but all of the computer records at MF were wiped out a few episodes earlier by the EMP, according to both the MF employees and CTU. The fact that they didn't get any information from the company except for the printouts Jack and Paul extracted was a major plot point a few hours ago, so even if a real EMP wouldn't do this, the fact that it's stated repeatedly in the show means it should hold true within the series; Chloe suddenly having information from them an hour or so later is discontinuous, and thus a mistake.

Shay

Day 4: 12:00 P.M.-1:00 P.M. - S4-E6

Continuity mistake: Day Four: 12:00 PM - 1:00 PM. When Tariq and Behrooz are shown in split-screen digging Debbie's grave right after the commercial break (12:54:10 by the show's clock), Tariq's white t-shirt is covered in dirt. When the shot goes back to them a minute or so later, Tariq's t-shirt is much cleaner.

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