I nearly became Sherlock Holmes’s sidekick instead. Before Doctor Who was even discussed I went to see Steven Moffat, the co-creator of the BBC’s Sherlock, to test for the role of Doctor John Watson. Steven saw me more as a Sherlock Holmes than a Watson, but the main part had already gone to Benedict Cumberbatch. However, Steven saw something in me that made him think I could be right for the role of The Doctor. How Matt Smith nearly became John Watson