Commodore Leon Crompton is the leader of US Navy Task Force 10. His job is to find and sink Wolf Pack Laika, which consists of eight German U-boats operating off the Azores.
The 918th is assigned under Colonel Gallagher as the Hunter portion of the team. He is to not carry bombs, but to fly only with enough arms to protect themselves. Compton's ships will be the killers. Gallagher assigns 9 B-17's , Crompton's force is 4 DD's, and 1 CVE.
Gallagher's bombers find the U-boats, when they come up for air. They report the position to the fleet, but before they arrive the U-boats return to the depths. The U-boats call for help and the Germans send up fighters not for the Navy, but for the hunters (the 918). Gallagher requests help from the Navy and the flight commander agrees to help, but Compton overrides him and orders him to stay with his own bombers. Gallagher loses two bombers.
While the officers fight with words, the enlisted Army and Navy men cause a bar brawl. It takes two enlisted Americans and a British female Corporal to bring an objective eye to Gallagher and Compton.
For the next mission, as Gallagher puts it, the Navy continues to be the primary hunters, as they have experience in hitting moving targets. But this time the 918 will be carrying bombs and will help sink, if they can. Crompton returns to his task force and decides to move his flag to the carrier, as the cruiser has yet to arrive. Just then the wolf pack attacks the task force and hits the carrier, which is now sinking. Major General Britt orders Gallagher to get there as quickly as possible.
Next we find the carrier sunk and the only air cover left are the bombers. Crompton remains on the destroyer and orders it to leave the task force. The Commodore tells Gallagher he will be using depth charges to force the U-boats up and Gallagher is to bomb everything including (if necessary) the U.S. Navy destroyer, but he's to get the wolf pack.
Enemy fighters arrive to protect the U-Boats. Gallagher thought this would be a turkey shoot, but they'll now have to work for the victory. General Britt orders Major Stovall to keep his squadron on the ground, as they won't be able to make it to the battle in time. Thus far the task force and Gallagher sunk three subs. Gallagher orders his men back to England when they no longer have bombs to drop.
Gallagher's plane is on fire and it looks to be a fuel line and they can't make it back to England. Gallagher won't ditch as it would mean losing half of his crew. He orders a bail out and the Commodore orders his boats into the water for immediate rescue operations. At the end of Act IV it looks like Gallagher wasn't able to make it out alive.
During the epilogue, we discover Gallagher's Father is now a Lieutenant General. The Commodore is calling him in Washington, DC to tell him his Son is still alive but badly wounded. He'll be returning to the states for medical leave / rest.
The series ends with Major Stovall taking command of the 918, Colonel Gallagher being ordered home for a medical leave / rest, the Commodore is taking Gallagher home on his new flag ship to his father, and General Britt stating when Gallagher returns he'll be allowed to continue flying.