Ashley Lazarus

The plot concerns high-sea hijinks aboard the Caribbean Star, a combination cargo ship and floating casino. In the midst of the high rollers and spinning roulette wheels appears Luis Carreras, an amoral mercenary who hijacks the ship. Taking his marching orders from a mysterious mastermind, he installs an atomic device mid-ship, holding both the passengers and the bomb hostage, hoping to exchange them for the gold bullion of an U.S. Treasury ship... (allmovie.com)

When the chips are down and everything seems lost, it's good to have a best friend. (imdb)