The mysterious Hemingway causes havoc at UNCLE headquarters in New York through various means, including tampering with the facility's water supply and electrical system. This occurs on the eve of an important conference where UNCLE will host leaders from around the world. Meanwhile, Thrush's Dr. Egret and Riley, a Thrush mole inside UNCLE, conspire to assassinate the leaders. Solo and Kuryakin try to figure out Hemingway's motives. Virtually the entire episode takes place at UNCLE headquarters.
—Bill Koenig