Doctor Who: The Invisible Enemy (Part 4)

"The Invisible Enemy (Part 4)" is the eighth and final chapter in the "The Invisible Enemy" serial, which ran through episodes 5-8 in series 15 of the television series Doctor Who. The episodes originally aired in six parts on BBC1 from October 1st to October 22nd, 1977. The serial was directed by David Maloney and written by veteran Doctor Who screenplay writer Terry Nation. In this episode, The Thal resistance fighters storm the Kaled bunker. The Doctor faces a strong moral dilemma and Davros makes his final move as the Daleks patrol the bunker corridors wiping out all opposition.