Let the conspiracy theories begin -- that alleged home movie of Marilyn Monroe having sex with John F. Kennedy and Robert F. Kennedy will not be going up on the auction block.

The auction, which was set for Tuesday, has been canceled because the owner of the 8-millimeter film,William Castleberry, settled his $200,000 debt.

Castleberrry, a memorabilia fanatic, owed the money for a previous court judgement against him -- and the Tulare County Sheriff in California had seized the film, along with several other items, to cover the debt.

Castleberry's attorneys tell TMZ they have no idea who made the payment -- but all of their client's possessions will be returned.