Revealing mistake: When Stevens leaves the house about halfway through and sits on a bench there is a modern electrical outlet on the wall to his left.
Revealing mistake: In the first scene with Lincoln and his cabinet in his office, in one close-up of Lincoln you can see that Daniel Day-Lewis has a pierced left ear, which Lincoln definitely did not.
Answer: Lincoln was shot at Ford's theater while attending the play Our American Cousin. The interruption by the manager to announce that Lincoln had been shot was during a different play that Tad Lincoln was watching at the time in a completely different theater.
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