Star Trek: Enterprise
A List of ST:ENT Episodes (Wikipedia)
Some fun (& interesting) ones:
G-Ser - Wikipedia - Mem-Alpha - IMDB
"Doctor Phlox and Captain Archer must decide the fate of two species suffering from an evolutionary pandemic."
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G-Ser - Wikipedia - Mem-Alpha - IMDB
"While answering a distress call, Commander Tucker is kidnapped along with a demanding alien princess."
Not hard Sci-Fi, but an entertaining episode.
G-Ser - Wikipedia - Mem-Alpha - IMDB
"Commander Tucker becomes comatose after an accident, and a rapid-growing clone is created for the purpose of harvesting brain tissue."
This may be one of the best pure Sci-Fi episodes in the whole Star Trek franchise.
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