The second of the popular Doctor series sees doctor Simon Sparrow (Dirk Bogarde) keen to escape the boredom of medical practice ashore and the threat of matrimony. Sparrow signs up as a medical officer onboard the cargo ship SS Lotus, pleased to be free of any female distractions. However, Sparrow soon falls foul of the ship's skipper, fearsome captain Hogg (James Robertson Justice) and worse still, lands in jail after a drunken celebration on arrival in South America. Two new passengers, Muriel (Brenda de Banzie), the daughter of the shipping-line owner, and Helene (Brigitte Bardot), a beautiful French singer, come aboard to pursue the Captain and Simon romantically.