Doctor in the House S06E01 - Sir John and Baby Doc

Dick gets the sack and Duncan resigns in protest. With Collier gone and the Binghams bringing up triplets they've nothing to stay around for and become ship's doctors on passenger liner the Begonia, only to find the captain is Sir Geoffrey's twin brother Norman. Next day they are shipped aboard by a crane to a very dirty ship whose last doctor died of suspected parrot fever and where they are likely to be pursued by crewman Mad Jake. Fortunately they find out in time they're on the wrong ship, it's not the Begonia after all.