Sarah and Harry instantly disappeared.
‘Yes... it should be all right,’ the Doctor smiled, abruptly disappearing himself. ‘Though one can never be absolutely certain...’ continued his disembodied voice from the now deserted circle.
Krans and Erak gaped in disbelief as the Doctor suddenly reappeared for a moment, his hat solemnly raised in farewell.
‘...Can one?’ he grinned, before just as suddenly disappearing again.
For a long time the two crewmen stood staring open-mouthed. But the circle remained empty in the gathering darkness...