The BBC, ladies and gentlemen.<-- Am I the only one that thinks, if there is ever a special where this happens, that Peter NEEDS to play old Sherlock! But I would love the Doctor to meet Sherlock<---they need to make a SuperWhoLock TV show
Matt smith originally auditioned for the role of sherlock in the BBC show, but Benedict cumberbatch was chosen over him. But Steven liked his acting so much he promised him a role in one of his shows. That show was doctor who.