“A group of martial-arts students is heading to an island that supposedly is home to the ghosts of martial artists who have lost their honor. A Hitler lookalike and his gang are running a female-slavery operation on the island as well. When the two groups meet, all sorts of crazy things happen, involving cannibal monks, piranhas, zombies, and more.”

https://www.imdb.com/title/tt0084573/?ref_=ext_shr_lnk