Tarzan the Mighty (lost action film serial; 1928)
Mary Brooks and her father are marooned in Africa by pirates, led by the Black John, who seeks to claim the Greystoke estate. To do so, he needs a locket held by Tarzan, raised by apes since birth, who is actually the rightful heir. John tries to kill Tarzan any number of times throughout the serial but always fails. Tarzan keeps Mary and her father alive, and when John appears in England to claim the title, he is stopped by Tarzan and killed.
The role of Tarzan was portrayed by Frank Merrill, gymnastic champion of 1918, who looked and moved exactly like the "paper" Tarzan. He was cast in the role after Joe Bonomo was forced to bow out after injuring his leg in an accident during a stunt. Frank had been doing stunt work before being cast in the lead role. and it was he who devised the vine swing for this serial.