Ep 30. The Day of Darkness (4)

Ian finds a way out of the flooded tunnel and into the burial chamber. He is later arrested however when he tries to save Susan who is to be publicly punished just prior to the next sacrifice. Autloc comes to believe that Barbara is a false god, but she convinces him that Tlotoxl is plotting against them. Ian faces his foe for one last time as the Doctor builds a pulley to re-open burial chamber door and get access to the TARDIS.