CT-27-5555 or ARC-5555 (nicknamed “Fives”) is a major character in the 2008-2020 animated series Star Wars: The Clone Wars.
Fives was a clone trooper who got promoted to ARC Trooper during the Clone Wars and a member of Domino Squad. He served as a member of the 501st Legion throughout the war until his discovery of the Order 66 conspiracy and meeting a tragic end on Coruscant.