Doctor Who is the longest running British science-fiction series on television.In fact,it holds the Guinness World Record.It began in 1963 and ended in 1989.The show was so popular,that in 2005,the BBC started filming new episodes.The new series is very popular.Over 25 countries broadcast it weekly.Doctor Who is about a man who calls himself "The Doctor" and travels through time.His time ship,the TARDIS,looks like a police phone box.Every week,he travels to different planets with his friends.They come face to face with many aliens and monsters.Their worst enemies are the Daleks from the planet Skaro.It is no surprise that Doctor Who is so popular .The episodes are full of action and adventure.Fans all around thr world can't wait to see what will happen next.