Lester, Dr. Janice

Caption: Spock confronts Dr. Lester as Kirk

Star Trek: The Original Series

Episode: TOS 079 - Turnabout Intruder

Brilliant scientist and James Kirk's former lover. Lester used an ancient life-energy transfer machine to swap minds with Kirk in 2269. Lester's charade as Kirk ended after ordering the entire senior staff executed.

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