Dad's Army (1968)

S3E10 Menace From the Deep

The platoon finds themselves on guard duty at a remote, abandoned pier for an entire week. Things take a turn for the worse when Pike mistakenly moors the boat, leaving them cut off from the mainland and without any food. Their efforts to signal for help using Morse code only attract Hodges, who rushes in to tell them to stop flashing the light, but ends up stuck with them as well. To make matters worse, Jones discovers a stray mine lurking beneath the pier. Will Hodges come up with a clever plan to save the day?