Nobody Is Norman Wisdom(1973)

Norman Wisdom played 'Nobody', a loser with no personality of his own. But when he puts any hat on, he adopted the characteristics of its owner. He had a girlfriend, Grace (Priscilla Morgan) and lived with his domineering mother (Natalie Kent), who didn't like Grace. Weekly, Nobody found himself in a different situation, playing a variation on his character. One episode had him as a character called Joe Nobody doing a brilliant impersonation of Peter Falk's Columbo; in another, he was seriously beaten by gangsters.