Continuity mistake: In the very last scene of the film Paul Newman ignores the ringing phone with Charlotte Rampling on the other end. A wide shot shows a paper coffee cup is on a table to his right, in front of the plastic lid. In close up, he reaches right, picks up the cup from out of shot, drinks from it and, judging by his arm positioning, puts the cup back in the same place. The next, and final, shot of the film is wider angle again. The lid is there, but the cup is now missing.
Character mistake: The mole Laura Fisher is paid off with a check dated Feb 1982. During the trail James Mason says the events happened 4 years ago, in 1976. That would be 6 years ago.