A plane parachutes a package containing rolls of film over Bomber Command headquarters. The package is collected and the photographs developed. In the main photographic room, the Squadron Leader identifies a new oil installation at Freihausen, a town on the Rhine river.

At Bomber Command, the commander-in-chief directs operations. He selects the town of Kiel as the bombing target for that night's main force. Receiving the photographs of Freihausen, he gives the order to divert one squadron to this new target. The order is passed through group headquarters to RAF Millerton.

At Millerton aerodrome, news of a mission spreads among the officers in the crew room, and the aircraftmen on the flying field. The final details of the plan are completed in the group captain's office, and preparations are put in place at the bomb dump and the armoury.

The men are briefed on their mission: the target is hidden in a wood but can be easily found by following a canal system. Dickson from crew 'F for Freddie' is named captain. Two planes will go in first with incendiary bombs to help the following bombers identify the target. The men disperse to complete their final checks, and collect call signs and target maps.

In the crew room, the men prepare for flight, mixing banter with mission details and calls for lost belongings. A lorry arrives and they are transported to the flying fields where they board their planes. One by one the planes receive permission to takeoff from a makeshift flight control in a caravan.

Nearing their target, the crew of F for Freddie descend under the clouds and identify their target with the aid of the incendiaries. They unload their bombs successfully but are hit by ground fire from the German defences, damaging the port engine and wounding the wireless operator.

Having lost contact with F for Freddie, the officers at Millerton wait anxiously for news of the plane as the weather worsens. F for Freddie finally makes it back to England, but is hampered by fog. Given the option of bailing out or attempting a difficult landing, the crew unanimously vote for trying to bring the plane down safely, which they succeed in doing.

The crew give a report of their mission and are debriefed by the intelligence officer. The officer phones a brief report of the successful mission into Group Intelligence and the mission is complete.