Dr Who: The Three Doctors

The Doctor and UNIT are called upon to investigate strange events surounding Dr Tyler's research into cosmic rays. UNIT HQ omes under attack by an alien force, and the Doctor has no other option but to call on his own people for help. . . The Time Lords too are under attack, frm a mysterious power emanating from a black hole in space. With power reserves failing, the only way they can can hep the Doctor is to find a way for him to help himself. . . Breaking the First Law of Time, the first and second Doctors are lifted out of their time streams and sent to Earth to help the Third. Between the three of them, they must find a solution to the threat that not only endangers UNIT and Earth, but also the future of the Time Lords themselves. . . Originally Transmitted 30th Dec - 20th Jan 1973