In the third episode of the TV series, both occasions where Dirk admits he's the stalker.
This exchange in the first episode:
Dirk: The circumstances of my first meeting with Mr. Edwards lead me to believe that he is a paranoid conspiracy theorist. [Flashback; Dirk is clearly following Mr. Edwards] Mr. Edwards:[Suspicious] Are you following me?! Dirk:[Cheerfully] Yes!
Had a crash then?" ... "Oh. You look like you've had a crash!" This is definitely how most British people would react in this situation.