Doctor in the House S06E08 - The V.I.P.

Duncan is dismissive of Mr. McArthur in front of fellow passenger Polly Roberts, an undercover journalist writing an article on the cruise. She complains about him to the captain, who tells him a Very Special Passenger has found fault with him. Duncan assumes this is McArthur and keeps out of his way. When Polly gets food poisoning, thanks to dodgy squid Dick bought for the captain's table, she is charmed by Duncan's concern and they bury the hatchet. Knowing she is the undercover journalist he is again rude to Mr. McArthur - who turns out to own the ship.