From Alistair MacLean, the writer of Guns of Navarone, & Where Eagles Dare comes Puppet on a Chain! The headquarters of a drug-smuggling cartel is the quarry of American narcotics agent Paul Sherman (Sven-Bartil Taube, Eagle Has Landed). Though the cartel's activities are centered in Amsterdam, Sherman's search for the headquarters leads to an island castle owned by an offbeat religious group. Sherman and his partner Maggie (Barbara Parkins, Valley of the Dolls) run into serious trouble when they try to gain access to the forbidden site.