Continuity mistake: At the end of the second level (Scotland The Brave) Cortez picks up a photograph of Crow and Khallos. In the next level (The Russian Connection) you see the picture being taken, and Crow and Khallos have switched places.
Continuity mistake: In the first level (Time To Split) a bridge is blown up followed by the Time Splitters' mother ship. In the sixth level (The Hooded Man) the mother ship is blown up then the bridge.
Bug: In the mission "Breaking and Entering" if you go into the ladies' restroom and look in the mirror, two stall doors are always seen as open.