"Shut up," Remus responded at once, as sharply as he could manage. It was hard to look into that bloodstained, exhausted face and see recognition in the eyes, see something like pleasure in the faint quirk of the lips. Sirius was glad to see him, and he was showing it freely, without the natural suspicion that he should be showing to a werewolf who had been brought here to force him to talk. That wasn't something either of them should be doing yet - not until they were certain it was safe.

"Follow my fingertip with your eyes," he continued, folding three fingers down so that Sirius could see only his index finger. "Don't move your head. And what was the name you wanted to give the Giant Squid during our first year at school?"

Sirius, Remus knew, would probably understand what he was doing, at least if he wasn't too addled by his - how long had it been? Weeks? Months? - of imprisonment and torture. This was the same procedure that Madame Pomfrey used to conduct for him when she collected him from the Shrieking Shack after each transformation: a test of eye movement, pupil dilation, the ability to follow simple directions. It was to make sure he hadn't sustained any concussions or other injuries that might affect his brain. Only in this case, instead of asking, "who is the current Minister for Magic?" Remus was asking a question that would tell him if Sirius's responses were being controlled by someone else. Someone who didn't know all of their stupid in-jokes from ten years of friendship.