The Knickerbocker Hospital's putative mission to help New York City's neediest gets its most interesting stress test yet in "They Capture the Heat." An earlier episode of The Knick showed hospital administrator Herman Barrow (Jeremy Bobb) getting his teeth plied out by his loan shark, Bunkie (Danny Hoch); now, one of Bunkie's lieutenants may need his leg amputated in the dead of the night, putting his boss in Barrow's debt for once. After seeing Dr. Algernon Edwards (Andre Holland) scrub in for surgery, Bunkie tells Barrow, "That black bastard better not get too familiar with my man if he don't wanna find himself hanging from a lamppost," and both Algernon and Thackery narrow their eyes in unspoken disgust—a flicker of solidarity between the two men never before seen in the hospital's surgical theater. It's a collision of two of the show's up-to-now isolated environs, and even Clive Owen's haggard, seen-it-all drug addict Dr. Thackery manages to be appalled by the stench surrounding Bunkie. It's been a pleasure watching Steven Soderbergh stress Thackery and Algernon's unspoken shifts in opinion of one another, and "They Capture the Heat" skirts it on the margins.