It was an age of empire, an age of contrast, and an age of dramatic change - and one which would determine the destinies of nations as well as of men. Captain Philip Blackwood of the Royal Marines rejoins his ship, HMS Audacious, in August of 1850, anxious to get back into action. "Per Mare - Per Terram" is the marines' motto. In the torturous heat of Africa, where they are sent to stamp out the remaining strongholds of slavery, and later, in the bitter war of the Crimea, Philip Blackwood and his men learn to obey it without question.

They were the men and women of the Royal Navy's Special Operations units. Carrying out lightning raids on hostile coasts, they became a navy within a navy - each handpicked for their individual skills, and all of them courageous. Against the mighty backdrop of World War II they performed their small but deadly operations - living often beyond hope, sometimes beyond mercy. This is the dramatic story of a handful of such people. The Volunteers.

The human torpedo, or chariot, is the ultimate weapon in a war, and only men of extreme courage or recklessness volunteer for the special operations missions requiring its use. Reeman has also written 22 novels under the pseudonym Alexander Kent.

It was in 1943. On the Black Sea, the Russians were fighting a desperate battle to regain control. But the Russians’ one real weakness was on the water: whatever they did, the Germans did it better, and the daring hit-and-run tactics of the E-boats plagued them. At last the British agreed to send them a small flotilla of motor torpedo boats under the command of John Devane. Devane had been in the Navy since the outbreak of war.

From the author of The First to Land, a novel set during World War II. They called them the Scrapyard Flotilla. After a quarter of a century of service, the eight destroyers had seen all kinds of action. Now they were to be used in raids to open the way for the invasion of Occupied Europe.

HMS Royston, Coastal Forces Depot Ship, is mother ship to a battered, war-worn bunch of MTBs and MGBs. New on board is Sub-Lieutenant Royce: commissioned for three months, sea experience three months in an Asdic trawler, and aged 20. His commanding officer is Lieutenant Harston, aged 23.

His predecessor has been killed in action 48 hours earlier and is now hardly remembered. The crew are all young - some very young - but all old before their time....

HMS Wagtail is a river gunboat, a ship seemingly at the end of her unusual life, lying in a Hong Kong dockyard awaiting her last summons to the breakers' yard. Commander Justin Rolfe is also seemingly at the end of his useful naval life, an embittered man, brooding and angry from a court-martial verdict. Then the offshore island of Santu is threatened with invasion from the Chinese mainland.

The old submarine-chaser USS Hibiscus, re-fitting in a Hong Kong dockyard before being handed over to the Nationalist Chinese, is suddenly ordered to the desolate island group of Payenhau. For Captain Mark Gunnar - driven by the memory of his torture at the hands of the Viet Cong guerrillas - the new command is a chance to even the score against a ruthless, unrelenting enemy. But Payenhau is very different from his expectations....

In November 1941, Lt Ralph Trewin, DSC arrives at Singapore as second-in-command of HMS Porcupine. To the shell-shocked Trewin, the gun boat and her five elderly consorts symbolise the ignorance and blind optimism he finds in Singapore.

There will be days when you wonder at and question some of the risks you had to take, the sacrifices you were forced to offer in the face of death. In Kiel Harbour, 1945, the war in Europe is at an end. But for Lieutenant Vere Marriott and the men of MGB 801, moored amid a nightmare of devastation, it is an uneasy, unsettled peace. New assignments ashore and afloat mean fresh tensions and conflicting emotions. For some, glory now takes second place to profit.

Adriatic, 1940s... Curtis was the pro. He could steer a sub through a saloon and no one would notice. Duncan was the grumbler, more at home in the Aussie Outback than twenty fathoms under the Adriatic. Jervis was the spit-and-polish man, who knew the correct way to die. And George, the Cockney, was the toughest of them all. Four men in the Royal Navy’s smallest sub, preparing the way for history’s largest invasion.

HMS Temeraire: latest and most advanced of Britain's nuclear submarines. When Temraire's trials are cut short and she is ordered to the Far East to reinforce the fleet against a threat from Red China, her captain, David Jermain, knows that this is no routine exercise in flag-waving. And once in Asian waters, he and his submarine find themselves involved in a hidden, undeclared conflict beneath the sea.

It takes a special sort of courage to serve in midget submarines, and Lieutenant David Seaton, commanding officer of XE16, needs no reminding of the perils involved. The little X-craft with their four-man crews have been used against heavy enemy surface units and important harbour installations. But in 1944, with the Allies poised for an invasion through France, a new and more hazardous role is given to Seaton's flotilla.

Hong Kong, 1941... To the residents and defence forces of the Crown Colony of Hong Kong, the war in Europe remains remote. Even the massive build-up of Japanese forces on the Chinese border cannot dent their carefree optimism. Yet one man suspects the truth. Lieutenant-Commander Esmond Brooke, captain of HMS Serpent and a veteran of the cruel Atlantic, sees all too clearly the folly and incompetence of Hong Kong’s colonial administration. To Brooke, attack by Japan seems inevitable.

February 1943. As the balance of the war slowly shifts in Britain's favour, Lieutenant-Commander Steven Marshall brings his battle-scarred submarine into home port. Captain and crew are exhausted after 14 months' continuous service, but for most there can be no thought of leave. If the enemy collapse in North Africa is to be exploited, every experienced man will be needed. Marshall must return to the Mediterranean, but this time to a very different kind of war.