Delancey is a lieutenant on the frigate HMS Medusa, which is just returning from Spain and bound for the dockyard at Chatham to be paid off. Delancey, with no interest and few friends in the service, anticipates a long period on half pay as he scrambles to find a new billet.
As Delancey relaxes in a tavern with other navy officers the subject of the incredible victory of Captain Henry Trollope, commanding the converted East Indiaman HMS Glatton, over a Dutch squadron. It turns out that Glatton is expected shortly at Chatham for an overhaul.
When Glatton arrives, Delancey goes on board to satisfy his curiosity about the placement of the large caliber carronades on the lower gun deck. In the process, he meets Captain Trollope and provides a solution to a technical problem involving the tendency of the carronades’ muzzle flash to cause fires on the gun ports. This favorably impresses Trollope and he offers Delancey the position of second lieutenant on Glatton.
As Glatton is readied to sail to join Admiral Sir Adam Duncan’s North Sea Fleet, mutiny hits Spithead and quickly spreads to The Nore. Just outside Spithead, Glatton encounters a French privateer and takes it but it is so badly damaged that it sinks and Glatton has to go into Yarmouth to land the prisoners. There the crew learns the fleet is in a state of mutiny and soon after Glatton rejoins Duncan’s North Sea fleet, Glatton, too, mutinies and returns to Spithead.
The officers differ on how to handle the mutiny with Delancey arguing for a non-confrontational approach and the first lieutenant, Alexander Grant, arguing that they should forcefully put down the mutiny. Trollope agrees with Delancey, which earns Delancey the enmity of Grant.
When the mutiny at Spithead is resolved, Glatton sails to rejoin Admiral Duncan. As Glatton sails, both Delancey and Grant notice a suspicious gathering of seamen. Thinking new Grant confronts them and mortally wounds one of them, dispersing the rest. Much to the surprise of Grant, he is ordered to stand court martial for murder. The Admiralty feels that in the aftermath of suppressing the mutiny at The Nore that they can’t afford to give the sailors cause to complain that an officer can kill with impunity. Grant asks Delancey to defend him.
Far from being a pro forma court martial, Delancey finds the prosecutor seems determined to convict Grant in order to make a name for himself. Delancey ultimately wins the case, and the enmity of the prosecutor, by pointing out that the sailor had died ashore and thus Grant should be tried under civil authority.
Glatton sails for the blockade off Texel with Delancey as her first lieutenant as Grant is awaiting trial.
When the Dutch fleet sorties, Glatton takes part in the Battle of Camperdown and Delancey distinguishes himself. The victory brings despair for Delancey. Each of the first lieutenants in the fleet is promoted to commander. Trollope awards this promotion to Grant because he feels that Grant is a superlative officer, he will loose a critical promotion due to his absence, and the promotion will vindicate Grant in the eyes of other officers. Delancey confronts Trollope over the damage he sees to his reputation by being the only first lieutenant not promoted. Trollope explains his reasons and offers to retain Delancey as his first lieutenant and explain to the other officers why Delancey was not promoted. Delancey resigns in anger.
Trollope still has respect for Delancey’s abilities and uses his influence to see that Delancey is appointed lieutenant and commander into the fireship HMS Spitfire stationed at Cork.
At Cork, Delancey is assigned to work with a frigate commanded by a very imperious, aristocratic officer, Captain Kerr, who takes every opportunity to demean Delancey, his background, and his ship. Eventually Delancey earns a grudging respect from Kerr.
The main issue confronting the squadron at Cork is the possibility of a French invasion. To that end Spitfire and Kerr’ ship, HMS Vulture, patrol the west coast of Ireland. Eventually they are alerted that the French have landed at Killala. When they arrive they find the main French fleet has already landed its troops and departed, however a late arriving 74, Hercule, is grounded on a sandbar and must await high tide to float free.
Kerr favors sending Spitfire for help while he keeps Hercule under observation but Delancey points out that he runs a risk of being accused of inaction. Delancey proposes using Spitfire as it was designed, as a fireship, to destroy Hercule while it is aground.
Kerr reluctantly agrees and defers to Delancey’s plan. Though Delancey’s plan goes awry at almost every turn his preserverance results in the destruction of Hercule and the accolades of Kerr.