成人快手

A great maritime mystery lies deep beneath the waters of the Channel Islands. On the morning of 19 February 1917, German submarine UC-18 opened fire on Royal Navy Q-ship the Lady Olive. As the U-boat drew near to assess the damage it had inflicted, the Lady Olive counter-attacked. Both vessels were said to have sunk. For decades, divers and historians have searched to discover their fate and understand the fascinating story that led to this encounter, but no-one has come close to finding the wrecks.

The documentary follows film-maker Karl Taylor and his specialist team over four years as they search to discover what happened on that fateful February day in 1917.

Principal underwater photography: Karl Taylor and Peter Frankland