Summary: Studio compilation showing a fictitious "action", which involves the various types of craft engaged in anti-submarine warfare duties.
Description: A torpedo track reveals the presence of an enemy submarine. A destroyer (Yarrow M Class), ML.55 and two companions, and a trawler, Electra, close in. Electra drops a primitive depth charge. The "U-boat", when forced to the surface, is clearly identifiable as the British submarine H.47, and is flying the White Ensign. A ship's cutter picks up "survivors". A small observation periscope emerges from a calm sea and passes off screen, as the enemy "submerges for the last time". Fish, stunned by the depth charge, are collected by the drifter's crew: "To-morrow will be Friday and we've got 'some' fish today."
