Warwick Deeping was a steam trawler built in December 1934 by Cochrane and Sons Ltd in Selby, Yorkshire. It measured 155ft 8in by 26ft 1in by 14ft 1in and had a gross tonnage of 445. It was powered by a triple expansion three cylinder engine and one single engine boiler, providing 111 nominal hp. Originally owned by the Newington Steam Trawling Company Ltd, Warwick Deeping was purchased by the Admiralty in August 1939. It was refitted as an anti-submarine vessel and armed with a 4-inch forecastle gun and a twin barrelled 0.5-inch machine gun.
On Friday 11th October, 1940, the Warwick Deeping, in company with a similar vessel, the Listrac, left Portsmouth to patrol around the Isle of Wight. The crew was 25 strong, commanded by Royal Navy Reserve officer John Bruce. By 10pm the two boats were approximately ten miles south of St Catherine's Point. The weather was recorded as calm and the bright moon gave good visibility of two to three miles.
Meanwhile, the German Torpedo Boats (more akin in size to Royal Navy destroyers than Motor Torpedo Boats) Falke, Grief, Kondor, Seeadler and Wolf of the 5th Torpedo Boat Flotilla set sail from Cherbourg to conduct an aggressive patrol of the Channel, in the wake of a bombardment of their port the previous night by HMS Revenge. At 10.35pm a lookout on the Warwick Deeping spotted ships on the port quarter. Within seconds the two ships found themselves under fire and splashes appeared around the ships. Listrac, wrongly believing they were friendly vessels, lit its recognition lights. Shortly after, it was struck by shells and such severe damage was done that it began to sink. The attacking German ships continued to fire at it until it sank. Eleven men died, five during the action and six more from their wounds.
About two to three minutes after the first shots were fired, the Warwick Deeping was hit for the first time. One shell wrecked the forecastle gun and another hit below the water line on the port side. An emergency radio broadcast was made and the ship began zig-zagging in a belated attempt to escape north. The German ships steered away, but went on to sink two French vessels later that night.
Warwick Deeping continued north. Bruce hoped he might be able to beach the ship on the Isle of Wight coast, but the bow was down and the ship was labouring. Twenty minutes later it was evident that this was a forlorn hope and the crew abandoned ship. The Warwick Deeping sank unseen, presumably in the early hours of the 12 October. A motor boat from Ventnor towed the crew's rafts to the shore; there were no casualties.