If It's Only in Your Head - S5-E24
Corrected entry: After seeing Dave's disturbing tape at the airport, Mike gets up to leave and tells the lady sitting nearby, "Excuse me. That woman I was with, tell her I had to go; it's an emergency." Seconds later when Katherine returns with their drinks, the lady tells her, "Your friend asked me to tell you he had to leave. He said to say he's sorry." However, Mike never said anything to the lady about being sorry.
Correction: That's a character mistake, not a show mistake. Perhaps she felt bad that he didn't apologize and added it herself, or maybe she just wasn't listening.
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