Conversation so far:
Where did Anthony McPartlin begin Anthony McPartlin's career?
McPartlin's first appearance on television was on the children's workshop programme Why Don't You?.
Was that the only show he was on?
but his big break came when he rose to prominence playing the character of PJ in the CBBC series Byker Grove.
Why was the show important to his career?
he rose to prominence playing the character of PJ in the CBBC series Byker Grove.

Question: What was a hallmark of his career?
Self-contained rewrite: What was a hallmark of McPartlin's career?