G
From Tardis Wiki, the free Doctor Who reference
As spoken by the Tenth Doctor and the entity possessing Sky Silvestry, G (Morse code: --. (TV: The Man Who Never Was) was the seventh letter of the alphabet, following F and preceding H. (TV: Midnight)
As the superhero known as the Ghost, Grant wore a suit with a big G on his chest. (TV: The Return of Doctor Mysterio)