Jon Pertwee played the third known incarnation of the Doctor. That's him on the right. On the left is his son, Sean Pertwee. For Halloween, the younger Pertwee dressed in his father's famous role.
Like his father, Sean Pertwee is an actor. When David Tennant left the show a few years ago, rumors circulated that Sean Pertwee wanted to replace him as serve as the Eleventh Doctor. In an interview with the Daily Telegraph, Pertwee described the origin of this rumor:
No, I never said I wanted the part, but there is a financial tale behind how the rumour started. For a laugh I tried putting a £50 bet on me to play the next Doctor because I thought I was in with a chance, but all the boys I knew in Islington decided I must have some inside info so they piled in behind me. When the betting shop staff asked who I was, the boys told them my father had played Doctor Who so they called head office about it and then declared all bets off. The next thing I knew I was in the news as running for the part, but I think it stemmed from trying to put £50 on myself. I'd love to have a guest part, but when it comes to the main role my father was too big an act to follow.
-via io9
http://www.bbc.co.uk/programmes/p01m3kfy