Cold Hands, Warm Heart - S2-E2
Visible crew/equipment: Barton is terrified by a plant-like alien floating outside his spaceship window. The Venusian critter might be a heck of a lot scarier if it bore less resemblance to a furry stalk of celery - and if only its puppet strings weren't showing. (00:25:45)
Behold, Eck! - S2-E3
Continuity mistake: When Dr. Stone's assistant helps him up from the floor, there's a lopsided, circular diagram drawn on the chalkboard behind them. One shot later, the diagram has changed into a perfectly round circle and has moved itself several inches higher on the board. (00:06:10)
Andro: Better to die than to sit and watch the world die.
The Forms of Things Unknown - S1-E32
Trivia: Part of Dominic Frontiere's haunting musical score for this episode later became the theme and background music for the TV series The Invaders, a show for which Frontiere served as the primary composer.