As in Ice Station Zebra and The Guns of Navarone, MacLean trots out his big hardware for an engineering adventure-spectacular, a kind of melodrama he could write with both arms in a cast and his mouth applied to a Cuba libre straw. The big stage set this time is a football-field-size oil rig anchored in the Caribbean and owned by super-millionaire Lord Worth, who has drilled into a fantastic oil bed and is upsetting world markets. The enemy is the big majors, who have formed a secret strike force, headed by the evil Cronkite, who has hijacked a Worth tanker, blown up another, and has $10 million with which to plan devices for atomizing the rig. Grenades and Schmeiser submachineguns roar back and forth on the concrete rig while rival helicopters and submersibles rattle sabres at each other. . . . Deja-viewing for only the most megatonically-minded.