During surgery, Thackery's hand is forced by Algernon, which irks Gallinger. A recovering Abigail regrets her involvement with Thackery and Sister Harriet and Cleary make a couple of deals. Meanwhile, Bertie receives a scolding from his physician father who is unhappy with his son's career path and Lucy becomes privy to Thackery's secrets.

Refusing to collaborate with Dr. Zinberg on blood-transfusion research, an increasingly paranoid Thackery pushes himself to the limit, and beyond, in an effort to “solve the riddle” and beat his rival. Cornelia and Edwards arrive at a crossroads; Barrow trades one creditor for another; Lucy requests Bertie’s help. With the Knick in the midst of yet another crisis, Robertson calls for a vote.