A U.S.S. Enterprise landing party beams down to an uncharted planet. The planet seems like a perfect candidate for shore leave with its "Earth-type" characteristics. McCoy's first encounter on the new world is with a life-sized white rabbit in a waistcoat, being chased by a little girl. Kirk beams down himself to find his old rival from his academy days, Finnegan. While trying to catch him, Kirk meets Ruth, an old girlfriend. Elsewhere, Sulu is attacked by a Samurai Warrior while others are chased by tigers and aircraft. As the perils become more and more deadly, Kirk and Spock realize that their thoughts are somehow coming to life around them.

Emily Banks (Yeoman Tonia Barrows)
Oliver McGowan (Caretaker)
Perry Lopez (Lt. Esteban Rodriguez)
DeForest Kelley (Dr. Leonard H. McCoy)
George Takei (Lt. Hikaru Sulu)
Bruce Mars (Finnegan)
Barbara Baldavin (Specialist Angela Martine/Teller)
Nichelle Nichols (Lt. Uhura)
Marcia Brown (Alice)
Sebastian Tom (Samurai Warrior)
Shirley Bonne (Ruth)

• Barbara Baldavin played Angela Martine in the previous episode, but was cast as Mary Teller in this episode. The mistake was discovered halfway through filming, which is why Kirk calls her "Teller" near the beginning and Rodriguez calls her "Angela" near the end.
  
• Kirk's shirt is ripped fighting with his annoying Finnegan.