Vice-Admiral Rolland was a British naval officer who served as Assistant Director of Naval Operations and head of MI6 during World War II.
He was the principal mastermind the plane to expose Nazi spies among their ranks, and together with Colonel Wyatt-Turner, he also planned Major John Smith's rescue of General George Carnaby. He remained in constant radio contact with Smith's group during the mission, and sent Wing Commander Carpenter to pick them up after they'd rescued the actor impersonating Carnaby and gotten the names of the Nazi spies.
When Wyatt-Turner went along, Rolland gave him a Sten machine gun with the firing pin removed, because he suspected the Colonel was a spy himself. He turned out to be right, and Rolland's sabotage of Wyatt-Turner's gun ended up saving the life of Smith aboard the plane.