Mary and Bobby Trevor are castaways befriended by Tarzan. When Lord arrives, looking for the family heir, Black John tries to fill that role and marry Mary in England. Tarzan shows up and marries her instead.
| Actor | Role |
|---|---|
 Frank MerrillTarzan | Tarzan |
 Al FergusonBlack John | Black John |
 Natalie KingstonMary Trevor | Mary Trevor |
 Bobby NelsonBobby Trevor | Bobby Trevor |
 Lorimer JohnstonLord Greystoke | Lord Greystoke |