Mysterious deaths of Enterprise crew on a desolate planet disrupt McCoy's unexpected reunion with an old love.
Kirk confronts two crew members (Gary Lockwood, Sally Kellerman) after a psychic force invades their minds.
A strange ailment which bares emotions afflicts the crew as the Enterprise observes a planet's disintegration.
A transporter malfunction strands Sulu and others on a frigid planet and splits Kirk into two antithetical people.
The Enterprise interferes with Harry Mudd's (Roger C. Carmel) new business, supplying wives to rich but lonely miners.