Doctor Who: 11 Most Memorable Companion Exits Of The Last Decade

10. Mickey Smith (The Age Of Steel)

Mickey Smith had a rough old time of it in the TARDIS. After being swallowed up by a dustbin and abandoned by his girlfriend Rose Tyler (who didn't given the opportunity to drop him in favour of a more exciting life with the Ninth Doctor a second thought), he then became a recluse after being accused of murdering her when she didn't return for a whole year and basically spent the rest of the time at her beck and call waiting for her next unannounced appearance. Suffice to say, he wasn't very happy about it. A silver lining is that it made for one of the most interesting companion 'journeys' of recent years, though, as viewers watched Mickey's turbulent transformation from your run of the mill idiot to a fully-fledged hero in his own right. After being compared to K-9 in the sense that he was only there to serve as the Tenth Doctor and Rose's "tin dog", he decided that enough was enough and the TARDIS trio's venture to the parallel universe in Series 2 would prove to be a particularly life changing affair for Mickey. There he was reunited with his beloved grandmother Rita Anne - who had sadly passed away on the 'real' world - and after encountering his brave alternate Earth equivalent, Ricky, and aiding him and his fellow Preachers in their fight against John Lumic's army of Cybermen, Mickey opted to stay on the parallel world in order to fulfil his potential - even though it meant he would never see Rose again. Although Mickey has returned to the series since, it was fitting that he got the chance to start again on a whole new world on which he finally felt like he belonged. The development of Mickey the idiot is one of the most interesting arcs of the Russell T Davies era and that's largely down to Noel Clarke's performance. As of The End of Time, Mickey is back on our world (he just can't make up his mind, can he?) and working as a freelance Earth Defender alongside his wife, Martha Jones, which brings us to...