It's so funny, it's a crime!

America's favorite Mormon sibling singing duo, Donny and Marie Osmond, made their starring film debut in this wacky Waikiki comedy. Upon boarding their plane to the Islands for a "big concert," a stranger gives the sassy, wise-crackin' Marie an ugly pukka shell and driftwood necklace that, unbeknownst to her, is the missing piece to a treasure map leading to a sunken U.S. submarine filled with gold bars!

They both rely on their musical variety show acting style, and still find time to sing some songs (including "Doctor Dancin'" and "You Bring Me Sunshine," and their duets are laden with the same snappy repartee that television audiences became familiar with on The Donny and Marie Show.

A gang of thugs go to all sorts of crazy lengths to get the necklace from the unassuming Marie; there are some close calls too, like when she finds her hotel suite ransacked, with a burglar three times her size riffling through her possessions -- the quick-thinking Marie throws oranges at him and beats him with a pillow until he runs away.

The toothsome singing duo, Donny and Marie Osmond, head for Hawaii in this comedy. The trouble begins when Marie acquires a lovely necklace without realizing that it is coveted by a group of thieves. An enigmatic woman is also after the necklace. Mayhem, music, and sibling rivalry ensue.

For their "big concert," Donny does a Polynesian slap dance -- wearing angel flights and a vest -- with a bunch of half-naked luau dancers from "Kalo's South Seas Revue," and Marie swings poi balls, does a hula, and performs a couple of Hawaiian tunes.

What happens next?