War-Gods of the Deep (1965) starring Tab Hunter, David Tomlinson, Vincent Price, Susan Hart, John Le Mesurier

War-Gods of the Deep is a delightful popcorn movie – not dreadfully deep, but eminently enjoyable. It deals with a trio (Tab Hunter, David Tomlinson, Susan Hart) staying at a manor on the  Cornish coast in 1903, where the house is burgled by … mermen? Who later proceed to kidnap the woman, sending the two men — and a chicken — in pursuit, where they find a group of smugglers, living deep beneath the sea, near an active volcano, and led by the iconic Vincent Price.