Thank you for supporting our journalism. This article is available exclusively for our subscribers, who help fund our work at the Chicago Tribune. It springs from many inspirations, notably Robert Bresson’s “Pickpocket,” but writer-director Paul Schrader has made the components his own and then some: an isolated man, alone in a room, writes in his diary while ruminating about the forces of darkness outside that room and inside his soul. Travis Bickle in “Taxi Driver,” written by Schrader, connects directly to Schrader’s most recent trio of pictures begun with the excellent “First Reformed” with Ethan Hawke; the Oscar Isaac-headed drama...