One of the greatest aspects of the US version of 'The Office' was the perfect chemistry exhibited by the ensemble cast with one another - everyone seemed perfectly cast in their roles, almost as if these were the parts they were born to play. But it could have turned out pretty differently...
Seth Rogen and Patton Oswalt for Dwight?
John Cho and Adam Scott for Jim?
Kathryn Hahn for Pam?
Bob Odenkirk for Michael?
It all could have happened - as seen in the original audition tapes, a LOT of familiar faces pop up, auditioning for roles that went to someone else. A lot of them actually seem like they would have been good fits - until you see the actors who DID get the roles, and remember how totally perfect they all were.