The one where the Doctor removes himself from the mind of Xoanon...
Pennant Roberts, a director new to Doctor Who, was not the best at fight or action scenes (prime evidence: Warriors of the Deep). The struggle at the start of this episode between the Doctor, Leela and the Tesh is staged quite clumsily, with very little natural fluidity. The stuntman was Terry Walsh, who I'm guessing also arranged the fight scene, but this time around Walsh fails abysmally, perhaps restricted by the set, who knows? The struggle ends with the Doctor pushing the Tesh against the wall, which Xoanon has made lethal, and so yet again the Doctor is responsible for somebody's death (albeit in self-defence).
Meanwhile, the Sevateem are making their way through the mouth of the idol towards the Tesh ship, and when Calib and Tomas see the (really unconvincing model of a) Mordee ship, they realise that the Doctor was right all along. The ship, to them, is the gateway to paradise, and it's both heartening and tragic to see everything seer Neeva believes unravel before him. He now realises Xoanon is his enemy, and is determined to seek revenge for his tribe.