Apparently the Doctor did want to communicate, because their departure was further delayed by the lid sliding open a little way, to reveal the Doctor’s face, which looked paler than ever in the sunshine.

He opened his eyes and attempted a smile.

Nyssa bent over him. ‘What is it, Doctor...?’

He blinked in the light. ‘I just wanted to say...’

‘Yes?’ Tegan drew closer too.

‘Er... Forgotten. Never mind, plenty of time.:. It’ll come to me.’

The sunlight seemed to be hurting his eyes, so Nyssa began to draw the lid shut. Then he blinked rapidly and said in a tremulous voice: ‘No, no... Remembered. Thank you. Wanted to say thank you.’