Donchaknow (often spelled differently) is a running phrase/joke which is used quite often in different shows of Have I Got News For You. The phrase is an impression of a stereotype of the English upper class twit. The phrase and the ""upper class twit accent" is often used by both Paul and Ian.
Ian claims that the phrase was started when he went to see one of Paul's comedy tours, without telling him, and saw Paul doing the impression. He says he found the impression was funny until Paul, during the performance, claimed it was an impression of Ian.
- Paul mocks Ian for saying that "he Going down the collider!".