But
but the time machine isn't destroyed in the end ...
shareI think we're supposed to believe that the damage to the time machine was cumulative and that the final trip blew it up, killing the "spare Frank" who was inside the building.
On the other hand, if it didn't get destroyed, that would be a pretty nasty ending, as Frank might figure out how to send himself back again.
Frank forced Brian to 'over tax' the machine, and if he did survive, there's no way he could figure out how the machine functions, if it were to have survived.
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