Susan Hart (born June 2, 1941 in Wenatchee, Washington) is an American actress, and the widow of American International Pictures (AIP) co-founder James H. Nicholson.
She is best known for her appearances in three popular AIP films of the 1960s, The Ghost in the Invisible Bikini, Pajama Party, and Dr. Goldfoot and the Bikini Machine as well as two other non-AIP movies, For Those Who Think Young and Ride the Wild Surf. In 2003, a Golden Palm Star on the Palm Springs, California, Walk of Stars was dedicated to her.
Hart now owns the rights to 11 movies made by her late husband’s company: It Conquered the World (1956) and its 1966 remake Zontar, The Thing from Venus, Invasion of the Saucer Men (1957) and its 1965 remake The Eye Creatures, I Was a Teenage Frankenstein (1957), I Was a Teenage Werewolf (1957), The Amazing Colossal Man (1957), Terror from the Year 5000 (1958), Apache Woman (1955), The Oklahoma Woman (1956) and Naked Paradise (1957).
The Ghost in the Invisible Bikini is the seventh (and last) of the American International Pictures (AIP) beach party films and was released in 1966. The entire film takes place in and around a haunted house with no beach in sight, with the teenage gang instead cavorting in and around it and the adjacent swimming pool. Besides the usual bikini-clad cast, random singing, silly plot line, musical guests, and ridiculous chases and fight scenes, the continuity linking this to the other beach films is the Rat Pack motorcycle gang led by Eric Von Zipper (Harvey Lembeck), as well as the appearance of previous beach party alumni Tommy Kirk, Deborah Walley, Bobbi Shaw, Jesse White, Aron Kincaid and Boris Karloff.
Pop singer Nancy Sinatra, who was on the rise at the time just before the film was released, has a supporting role and performs one song written for the film; and the Bobby Fuller Four appear as themselves and sing two songs. Claudia Martin, daughter of Dean Martin, co-stars in the film as Lulu. The briefly famous Italian starlet Piccola Pupa appears as herself and also sings a song.