the tell he can't switch off

Marathe's cover includes a fake sniff, a small piece of business meant to sell the addict — and it has escaped his control, firing "from nowhere," repeatedly, throughout an interview where he is otherwise flawlessly deliberate ("pretended that it was necessary to sniff"; "smiled with desperation and pretended to sniff"). The concealer is betrayed by his own instrument of concealment: a performed tic that has gone involuntary is now a genuine tell he can no longer source, the disguise developing a symptom of its own.