The LCS was part of Operation Bodyguard, a deception tactic designed to make Nazi Germany believe the Allies were planning to attack them through Finland. Likewise, the LCS was involved in Operation Graffham, aimed at convincing the Nazis that the Allies intended to invade Norway.
In 1943, Wing Commander Douglas Quilter was put in charge of Operation Hellfire, the mission by the LCS to track down the escaped occult Nazi defector Ernst Littmann. However, in this instance, it was the LCS who had been deceived by their German equivalent. Littmann did not exist and all information regarding him was fake.
Nevertheless, Hellfire allowed the LCS to take down a cell of British fascists led by Sir Davenport Finch, and root out a traitor in Daisy Chapel, who had posed as one of their own. With the help of the Third Doctor and Jo Grant, who received the approval of Winston Churchill himself, the LCS exposed the fascists' schemes to force Britain's surrender, and also recovered the Amulet of the Wastelands, a Time Lord artefact. (AUDIO: Operation: Hellfire)