‘Is This a Room’ A pause-for-pause, cough-for-cough rendering of the F.B.I. transcripts of the first interrogation of the federal contractor Reality Winner, who is now serving a more than five-year sentence for whistle-blowing. The director Tina Satter turned this exercise in theater vérité, in which the blandest conversational clichés come loaded with unspecified menace, into a Kafka-like nightmare with a tension level worthy of Hitchcock. And as the beleaguered, unwittingly self-sabotaging Winner, Emily Davis gave one of the season’s most riveting performances.