Henry is sick, Shawn tells Gus. He called to cancel their weekend camping trip in the mountains and Shawn couldn't be more thrilled, until he catches his dad driving through town, the picture of health. Now Shawn has to know why he was ditched, and he and Gus follow Henry to the Monarch Lodge, where they discover Henry is a member. After Shawn perfectly repeats the secret handshake, they enter the lodge to find Henry in a room full of robed lodge members, surrounding a dead body on the floor. The brothers have called Henry in for help, but he insists he's retired both from the force and the lodge and calls the police. Gus, meanwhile, realizes he's in a room full of doctors, and gingerly steps around the body to start networking. Shawn tells Henry that the deceased, Arthur Holmstrom, was murdered, possibly by poison, and no one in the room seems to be upset about his death. Henry's friend Ted Archibald, who called them in, is worried they did something wrong during Arthur's Patriarch ceremony. He had a ceremonial hood on for twenty minutes, and is worried Arthur might have suffocated. Lassiter and Juliet arrive at the scene. It turns out Lassiter has always wanted to be a member but has been blackballed by his soon to be former father-in-law, Irving Parker. Now Lassiter is determined to solve the case quickly to impress Irving and the rest of the lodge members. Meanwhile, Gus has been busy locking down an appointment with Dr. Downs, who has a large practice and is a big purchaser of pharmaceuticals.