Watch: Billie Eilish gets grilled by Rainn Wilson.

Billie Eilish is a very well-known fan of the US version of ‘The Office’ - having watched the entire series twelve times! Billboard sent Rainn Wilson - who plays the character Dwight on the show - to her house to surprise her, and sit her down to give her an Office related quiz.

Wilson is incredibly funny, poking around her house and purposefully mispronouncing her name, while Billie laughs in response and shows off her Office door sign. The interview came about after Billie sampled some dialogue from 'The Office' in her song 'my strange addiction' - taking snippets out of the 'Threat Level Midnight' episode, where the charcters make a film based off a script they discovered five seasons earlier.

Billie openly jokes about how nervous she is, even turning away from Wilson at one point to try and get an advantage in answering the questions. 

Check out the hilarity below…