YMMV / Star Trek S1 E19 "Tomorrow Is Yesterday"

• Aluminium Christmas Trees: Spock says the fighter approaching them may be armed with nuclear warheads. There was in fact an air-to-air nuclear missile in service at the time.
• Hilarious in Hindsight: When Kirk explains they've traveled back in time by accident, Captain Christopher snarks that they seem to have a lot of those. He's referring moreso to accidents in general (since the destruction of his plane was also an accident), but given that Starfleet eventually creates its own Time Police to sort out all the temporal messes created by Starfleet officers, he's more right than he knows.
• Ho Yay: This episode is famous in the fanbase for showing it's not just women Kirk flirts with when he's trying to get out of trouble.
• Special Effects Failure: It turns out that optical effect of the Enterprise doesn't work very well against the sky. It can be pretty laughable when they say they're going incredibly fast and then we see the ship looking like it's barely even moving.

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