It is a show that has been around for 50 years this November and it is about a humanoid alien who travels through time and space with various companions in a time/spaceship that is seemingly forever stuck in the disguise of a blue london police box, he battles mostly with his wits against various monsters both human and alien to solve problems at the location of where he winds up(no control on where he goes) very rarely resorting to being physically involved(in theory) aside from sometimes a little sabotage, he has been played(officially) by 11 actors to date with each version having a different personality and appearance while in essence still being the same person he was originally. His mainstay villains(again some human) are Daleks, Cybermen(my favorite), Silurians to name a few and the new series will see the return of a classic monster/villain not seen since 1974 in the 3rd doctor's penultimate story.
Oh and nowadays there is alot of running.