Gunnar was played by Walter Koenig, who would go on a few years later to play Chekov on the original Star Trek (1966) television series.
Brooke Bundy, who debuted in the early '60s in The Donna Reed Show (1958) as one of Jeff Stone's girlfriends, has continued to stay very busy in an acting career that has spanned at least six decades. During the '65-'66 television season she appeared in six different guest spots on as many different series, her appearance in Gidget (1965) being just one of them.