Appearing in a dark room was definitely not Oliver's favourite thing, especially when he had absolutely no idea what world--or even what sort of world--it was on. He was startled enough already that he jumped rather spectacularly at the voice, quite as surprised as Leela was. It took him a second to realise who it was. "Leela!?" he called. "Where are we?"

It was a reflexive question to ask when you were in the dark. Considering where he'd been appearing up until now, he at least knew that Leela being here meant he was on her world--but he gasped as the realisation hit him. He knew what Leela's world was. "Is this...is this Gallifrey!?"