Secret Service agent Vance Markham cautiously enters a circus warehouse and looks around. The lights come up, revealing a chuckling man dressed as a magician seated in a throne. Markham draws a gun and prepares to shoot him, but the man in the throne calls to Julio... a ventriloquist dummy belonging to Villar. Villar knows that Markham is a Secret Service agent as does the magician. The light on Villar fades out and then comes up on Tony, a man with a knife. Tony figures that the agent is Jim West, but the magician knows better. The next light comes up on Miranda, who whips the gun out of Markham’s hand.
The next man to step out is Deadeye, who wonders if Markham is Artemus Gordon. The magician knows that Markham was supposed to meet Jim and Artie there and pass on the information he’s acquired. Markham tries to run but a strongman grabs him and the others close in.
A short time later, Jim and Artie arrive and discover that the door is unlocked despite what Markham said. They quickly burn out the lock with a miniature blowtorch and enter the warehouse. They split up to find Markham and Jim hears a choking noise. He tosses up a flare grenade and sees Artie suspended in mid-air by a hangman’s noose. Jim shoots through the rope, saving his partner, who sprains his ankle when he falls. They see Markham sitting on a barrel and hear him call them over. However, when they go over, they discover that Markham is dead with a knife in his back, pinning a poster in place. The boss’ voice rings out, taunting them and then chuckling.
The agents’ superior, Colonel Armstrong, comes to see Artie at the hospital where he’s being treated for his sprained ankle. Jim translates the poster for Armstrong, explaining that it is an invitation to the Eco Amusement Park. Armstrong wants answers and Artie explains that Markham was murdered by the Eccentrics, a band of thugs specializing in assassination for hire. No one knows what they look like, but rumor has it that they have been hired to assassinate President Juarez of Mexico. Armstrong is unimpressed with their lack of progress and asks what Jim plans to do next, and the agent says that he’ll be visiting the amusement park.
At the park, Jim rides in and hears the sound of crowds. However, he discovers that the park is abandoned and the sounds are coming from a phonograph record. The Eccentrics’ leader steps out and introduces his underlings. The magician makes Miranda disappear inside of a cabinet and then invites Jim to fight the strongman, Titan. Tony and Deadeye flank the agent, who realizes that he has no choice but to fight. Jim goes up on stage and launches a sneak attack. Undeterred, Titan comes back and tosses Jim around, but the agent finally subdues him. The strongman scurries off beneath the stage and the magician nods to Deadeye. The marksman goes after Titan and finishes him off.
Jim asks for his reward, the crown, and Miranda hands it to the agent. He realizes that it’s a fake and the magician assures him that they’ll make it up to him and make sure Jim gets what’s coming to him. Jim attacks Deadeye and Tony, but the magician makes Jim disappear in a puff of smoke.
A few seconds later, Jim drops out of a hidden shaft into the Eccentrics’ underground lair. After a few seconds the five remaining Eccentrics enter and the magician activates the lights with a few mystic gestures. The magician introduces himself as Count Mario Vincenzo Robespierre Manzeppi, chief of the Eccentrics. Manzeppi wants Jim to serve as Titan’s replacement and promises him unlimited wealth in return for his loyalty. His alternative is death and Jim quickly accepts. However, Manzeppi wants a test of his new loyalty: Jim is to kill Artie. Everyone but Miranda bursts into laughter.
Once the laughter dies down, Manzeppi summons an image of Emperor Maxmillian and his wife Carlotta. Jim notes that Maxmillian was shot dead by revolutionaries four years ago, and the emperor’s cousin Archduke Charles Louis plans to accept the crown... once the Eccentrics kill Juarez. Jim goes for one of the knives that Tony threw but Deadeye shoots first into the wall ahead of him. Manzeppi regretfully says that Jim will have to be taught a lesson and Tony offers to assist. The count agrees and Jim is placed into a box with a bullseye above his head. Tony misses his first two shots, going left and right. He hits the bullseye on the third throw, dropping Jim through the bottom of the box and into a cell.
Jim uses a miniature grappling hook and a discarded piece of rope to climb up, but Miranda opens a panel in the wall and invites him to follow her. Jim accepts and she leads him out, and explains that she wants to resign. The agent takes her with him, unaware that the Eccentrics are watching them on a televisual device. Manzeppi is satisfied that everything is going well.
At the Wanderer
, Artie hears someone at the door and draws a gun, and then lets Jim and Miranda in. Jim tells his partner that the Eccentrics plan to kill Juarez for the Archduke. Artie tries to send a wire to Washington but discovers that the line is dead. The Eccentrics emerge from the back of the car and Manzeppi expresses his admiration for the train. He congratulates Miranda on her performance and tells the agents that he’ll require their train. Manzeppi explains that he plans to keep them alive and present them to the Archduke as Juarez’s assassins. He then reminds Jim of his previous initiation to kill Artie, and tells him that once Jim is presented as Juarez’s assassin, it will appear that the U.S. supports the Archduke and the Mexican Empire. Jim offers them double their $1 million fee to save Juarez and his democracy. Manzeppi congratulates him on trying to divide and conquer but says that it won’t work... he thinks.
The agents knock out the lights and attack the Eccentrics. Artie escapes through a secret passage but Manzeppi seals the door with a gesture, preventing Jim’s escape. Manzeppi loses his temper and says that they have just enough time for a lesson.
Back at the amusement park, the Eccentrics place Jim in a platform with stylized woman’s hands. The hands close, trapping Jim in, and Manzeppi raises it into the air. The rope starts to split due to a chemical treatment. In 14 minutes, it will part, dropping Jim into the electrical grid below. The Eccentrics depart to kill Juarez but Miranda comes in and offers to split the $2 million that Jim promised. Jim agrees and tells her to smash the lights, but the grid destroys the pole that she uses. He has Miranda cut the electrical wires with the whip, despite the fact they’re right next to the rope. She nervously strikes and parts one wire, and Jim manages to leap clear just in time. They ride off to Juarez’s secret headquarters, which Manzeppi has already found.
Jim and Miranda ride up to the gates of the presidential palace and try to talk their way past the guard. When that fails, Jim prepares to jump him but the man summons two more guards. Jim rides off with Miranda, goes down the road, and then they climb over the fence. Artie, posing as a guard, spots them and escorts them to Juarez. Jim explains who he is and warns that there will be an attempt on Juarez’s life. A bookcase opens behind them and Manzeppi, Tony, and Villar emerge from a secret passage. Manzeppi announces himself and “Juarez” draws a gun. The count then reveals that Juarez is Deadeye in disguise.
Manzeppi plays the violin for the tied-up agents and Miranda. He then explains that he anticipated Miranda’s betrayal and made sure that Jim could escape. Now he has them where he wants them and plans to kill them once he disposes of Juarez. Manzeppi goes to take a nap, leaving Deadeye, Tony, and Villar on guard. Jim asks Tony for a demonstration but Deadeye objects. Tony ignores Deadeye and Jim stands by the door and invites him to throw. The knife-thrower narrowly misses a half-dozen times over until he runs out of knives, and Jim cuts himself free on one of those. However, Deadeye draws and stops him. Manzeppi comes out and Villar tells him that Jim suckered Tony into throwing his knives. The count then tells Deadeye to dispose of Tony, and the gunman obliges.
The count tells Jim that Deadeye is a machine but Jim is unimpressed, pointing out that all he’s done is shoot down defenseless men. Deadeye takes offense and ignores Manzeppi’s warning that Jim is trying to bait him. The gunman gives Jim one of his guns and Manzeppi realizes that he can’t stop his underling. Jim continues to bait Deadeye until h goes for his gun, and then guns him down. Manzeppi produces a small bomb and warns that if he’s shot, it will go off and kill everyone in the room. The crowd cheers outside and they realize that Juarez has arrived. Jim points out that he doesn’t know if it’s a bomb and Manzeppi asks if it’s worth the risk. He then departs through the bookcase passageway with Villar, closing the door behind him just as Juarez arrives.
Later, Armstrong and the agents go over the room but find no trace that the bookcase opens or that there is any passageway. The colonel thinks they imagined the entire thing. Meanwhile, a portrait of Juarez on the wall slides away and Manzeppi reaches through a slot, takes a rose, and replaces the portrait with one of his own.