Contains spoilers for this episode and earlier episodes.
Cooper and the deputies return to Owl Cave and find that someone has already moved the lever, exposing a much larger design. The tracks point to Windom Earle. Andy begins copying the image while Cooper asks Major Briggs to investigate Earle's time with Project Blue Book. Briggs recognises elements of the drawing from his own disturbing memories and agrees to help despite the secrecy of his work. A line Shelly repeats from her mysterious invitation alerts Cooper to a poem he once sent Caroline. Leo's handwriting then connects Earle's threats to the missing trucker, bringing the separate inquiries much closer together.
At his cabin, Earle tells Leo and a young visitor about the Black Lodge and the power he intends to obtain there. The visitor expects beer and a party, but Earle forces him inside a large chess piece and kills him with a crossbow. Leo's attempt to resist ends with another shock from his collar. Catherine and Pete open Eckhardt's puzzle box and find another box inside. Cooper takes Annie onto the lake, where they kiss while Earle secretly watches. Audrey's romance faces an interruption when John learns of trouble in Brazil and prepares to leave. At the park, Cooper and Truman open a mysterious crate and discover the murdered man's head inside the giant pawn, with a warning that the next victim will be someone they know.