The story follows the Royal Navy Flower-class corvette HMS Compass Rose under Captain George Ericson (Jack Hawkins), a Merchant Navy and Royal Naval Reserve ofﬁcer who has been called to active duty shortly after the outbreak of World War II and moulds an inexperienced crew into an effective and disciplined fighting force, from the dark days before Dunkirk through to final victory.
His newly commissioned sublieutenants, Lockhart (Donald Sinden) and Ferraby (John Stratton) are inexperienced and his ﬁrst lieutenant (“No. 1”) is James Bennett (Stanley Baker), a cowardly, hectoring martinet.
The Compass Rose (K49) leaves harbour for sea trials and three weeks of training for her inexperienced crew. This proves a baptism of fire, as they are battered by storms and encounter their first U-Boat.
As the war rages, the corvette makes numerous escort runs in the North Atlantic, often in terrible weather, and its men soon coalesce into a tough and competent ﬁghting force who succeed – with many losses of life – in helping to defeat the U-Boat threat.
After nearly three years on the water, the Compass Rose falls victim to a torpedo attack and sinks.
Forced to abandon ship, most of the crew drown or die from hypothermia. Taking to a couple of rubber life rafts, Ericson survives along with Lockhart and a few sailors.
Ericson is promoted to Commander, and with Lockhart as his ﬁrst ofﬁcer, takes command of the HMS Saltash Castle. Leading an anti-submarine group they continue their escort duties and late in the war – while serving with the Arctic convoys – they track and ultimately destroy U-53.
As the war ends in May 1945, the Saltash Castle returns to port, sailing past the surrendered U-boat ﬂeet, prompting Ericson to reﬂect on the fact that his commands were only able to sink two enemy subs over a more than ﬁve-year period.
Eight years after the end of WWII, Michael Balcon’s Ealing Studios brought Nicholas Monsarrat’s best-selling novel to the screen, launching the careers of Donald Sinden, Denholm Elliott and Virginia McKenna and also establishing Jack Hawkins as a star.
The screenplay doesn’t avoid showing the futility of war, and emphasises the emotional and psychological damage inflicted by war: several officers turn to drink, an officer has a breakdown, a rating calls the Captain “a bloody murderer” and Ericson himself cries when his decision to depth-charge a U-Boat results in the death of British sailors.
In fact, this was a rare reaction to the usual ‘stiff upper lip’ heroics of many British war films. It is also a prime example of a documentary style lending authenticity to the fictional story.
The fictional HMS Compass Rose was actually the HMS Coreopsis (K32) – a badly dishevelled Flower-class corvette loaned to the Royal Hellenic Navy. The ship was discovered in Malta where it was about to be scrapped. After undergoing repairs, K32 steamed back to England under its own power in June 1952, where it was refurbished and transformed into the Compass Rose with the majority of ﬁlming taking place on board. The ship was scrapped a year later.
The scenes of the ship at sea were ﬁlmed in the English Channel just out of sight of land in summer waters generally too calm to effectively portray conditions on the Atlantic Ocean in winter. For those scenes, the ship was taken to a tidal race off the tip of the Island of Portland. Though close to shore, a sandbar and a number of converging tidal streams provided the rolling seas needed for realism.