A woman comes into town and a largish woman, Kitten Twitty, disembarks, as the local children laugh at her. She goes in and gets a hotel room and Jim West, who is staying at the hotel offers to help her with her rather heavy bag. Once he leaves to get a shave, Kitty opens the bag to reveal… Dr. Loveless.
Kitty listens for Jim and fixes the water in his shaving basin while Loveless gloats that he will cause the agent to hallucinate. They watch Jim in the next room through a one-way mirror as he shaves. Jim suffers from brief searing head pains He collapses on the bed then looks up to see Loveless on the window sill, taunting him. Loveless holds him at bay with a gun until Jim gets the drop on him, shoots him, and the doctor falls into the street below. Jim goes charging out only to find that Loveless' body has disappeared and no one seems to have noticed anything.
Another stagecoach rolls into town and Artie gets out of it, and Jim expresses doubts about what's happened. As they go inside, Loveless gloats from the balcony above. Artie wonders if Jim is obsessed and examines a note that Jim received saying that the writer will hand Loveless over to Jim that night at a stable… a note written by Loveless. Jim has another head pain and douses himself with more water from the basin, then insists on going with Artie to check out the meeting site. There's nothing at the stable until Jim gets a brief glimpse of Loveless laughing at him. Artie suggest Jim go back to the hotel until that night and Jim briefly snaps at him before leaving.
That night Jim returns to the stable, haunted by Loveless' laughter. When Artie tries to keep him from running off again, Jim guns him down. Shocked, Jim runs back to the hotel and tells the clerk to call the sheriff. However, the clerk says there was no stagecoach and Artie isn't due to arrive until tomorrow. Jim goes to his room and then collapses, and Kitty and Dr. Loveless come in to gloat.
The next morning Artie arrives in town and the hotel clerk tells him that Jim was taken to the local hospital. Jim wakes up in the hospital to find Dr. Loveless seated above him. Loveless eventually brags to Jim that he plans to kill every person in America.
Artie rides to the hospital but the patients attack him and reveal they're Loveless' goons. The doctor comes out and takes him to Jim, who is relieved to see his partner alive. Jim figures that he hallucinated the whole thing and plans to do the same to everyone in America. Loveless enters, accompanied by Kitty and Antoinette. They maintain their disinterest to get Loveless to brag until Loveless threatens to drug Artie. Jim relents and asks Loveless to prove it will work on large groups. Loveless tells Kitty to mix the drug in with the staff's wine for dinner that night. Loveless and Antoinette leave and Jim points out to Kitty that Loveless is a ruthless killer. Kitty doesn't believe Loveless will go through with it and she believes he loves her and will make her pretty.
That night Jim and Artie are put in a cage in the room next to the dining hall and enjoy a meal. Antoinette and Loveless sing a duet while the staff kills each other in the next room, and Kitty reacts in horror. Once the men are dead, Loveless boasts to himself in a mirror where he sees himself as a normal-sized man. Kitty confirms the men are dead and Loveless explains that with the end of winter, he plans to release ducks with pellets of the drug on their feet. They are escorted back to their room but Jim grabs a turkey leg and has Artie eat it. They then make a dart out of the bone and rig a catapult with a pair of suspenders. At the nearby lake, Loveless is preparing the ducks for release while Jim and Artie lure Loveless' deaf-mute man-servant in and take him down. They go out into the cage but they can't get past the lock. They ask Kitty for help and she still believes Loveless will make her beauty, but they point out she won't have anyone to admire her once Loveless has killed them. She sobs in despair and inadvertently pulls the bars apart. They slip out and Jim and Artie slip out, while Antoinette discovers what has happened.
Jim and Artie confront Loveless in his laboratory but he threatens to throw the lever releasing the ducks. Jim and Artie manage to catch the weighted lever while Loveless, Antoinette, and Kitty head to the lake. The agents manage to wedge the lever in place and go out, to find the trio escaping in a boat. Jim shoots a hole in the boat and neither Loveless nor Antoinette can swim. Kitty can't swim either and the boat goes down, apparently drowning the three. Jim goes out to find them but can't locate the bodies. Jim admits he'll miss the doctor. As they leave, ripples spread out from where the boat went down…