Plot

Jim and Arte must stop Torres - a dangerous man in black more metal than flesh, with superhuman strength, the power of hypnosis, and a taste for revenge - from killing President Grant.

Jim and Artie work to protect President Grant, who is the target of Torres, a mechanically-enhanced former soldier who holds Grant responsible for his being caught in an explosion that forces him to design his own enhancements and turn himself into a 19th century cyborg.—Gislef

On the docks, a man dressed in black walks into a ship chandler's shop belonging to Ralph L. Gilbert. The man tries the door and finds it locked, and breaks through with one punch. The owner, Gilbert, stares at the man, Torres, who says that Gilbert is in an odd business for a retired Army colonel. Gilbert stares at Torres' partially metal-plated face and asks who he is, and Torres admits that it's difficult to recognize him now and says that he was a presentable young man. The owner finally recognizes Torres and is surprised that he recovered. Torres says that he is now a superior man, plated with iron and with iron cords for sinews. He says that the others made him as he is, and Gilbert swears that he has no idea what Torres is talking about.

Torres asks why Gilbert is hiding, and Gilbert says that he earns his living there. He asks what Torres wants, and Torres says that he wants the small thing of Gilbert's life. Gilbert grabs a pike and asks how he harmed Torres, and says that five of the officers dying in their cadre was a coincidence. He stabs Torres but the pike shatters on Torres' metal-plated chest. Torres chokes Gilbert to death, and tells him that that he now has his gratitude.

Jim comes in and sees Torres, who advises him to leave. The agent attacks Torres but his blows bounce off of Torres' body. Jim draws his revolver but the bullets have no effect. Torres reaches for Jim, who uses a smoke pellet hidden in the butt of his revolver to drive Torres out. Jim goes after him but Torres disappears into the fog.

A week later at the Wanderer, Jim and Artie gets a Morse code message that President Grant wants to know what progress they've made finding Gilbert's killer. Jim wonders why would anyone would want to kill Gilbert, and Artie's contacts have only tracked down Gilbert's niece Nina to a school somewhere out East. She's the only lead the agents have. Another message comes in saying that Nina has left school, and they figure that Nina is heading to the shop.

The agents go to the shop and find Nina there. They introduce themselves and she asks what they've discovered, and they admit they haven't found the killer yet. Nina suggests that Gilbert was the target of an assassination plot, and she has a photograph of the eight junior officers in her uncle's regiment. Six of them have violently died in the last year, and Gilbert sent her the picture and a letter saying he feared he would be next. Grant is in the photograph, and Army Intelligence received a similar letter from Gilbert. Nina insists on finding her uncle's killer, and Jim says that they've discovered that the regiment's doctor, Meyer, is practicing in the city and he would have intimate knowledge of the cadre, that wouldn't appear in the dossiers. Nina has identified one of the men in the photo as Lt. Torres, and she's heading to his villa on the Texas border.

Nina goes to Torres' villa and knocks at the door. Torres tells Maria, the old woman who answers the door, to let Nina in. Jim confronts the driver as he's leaving despite Nina's orders to wait, and the agent draws his gun on him and confirms where the man took Nina. When Jim turns his back, the driver draws a knife, but Jim senses the attack, turns, and shoots the driver, then rides to the villa.

Artie meets with Meyer, who says that Torres was self-taught and designed the operations that Meyer conducted on him. Meyer says that Torres should have died in the explosion, or in the succeeding operations. According to Meyer's dossier, Torres was on guard duty the night of the explosion. Meyer says that Torres was in agony for many years afterward, and sedation or anesthesia had any effect on him because of the nature of his injuries. Torres learned autohypnosis to suppress the pain, and Meyer performed the operation on Torres while he was conscious. Meyer confirms that half of Torres' bones are now metal.

Torres confronts Nina, and comments on her lack of reaction to his partially metal-plated face. She says that she has done her postgraduate work in psychophysics, and doesn't find it a dreary subject. Nina asks if Torres recalls her uncle. He says that he does and offers his condolences, and Nina says that she doesn't believe the death of the other six men was a coincidence. Torres talk about how charming is, and asks her to describe regression while he spins the light from a lamp into her face. He hypnotizes her with the lamp and tells Nina that she will gratify every wish and whim, and never waste a moment on serious thought, and tells her to laugh as a child. She busts into laughter,

Jim breaks into the cellar, setting off a hidden alarm that warns Torres. He leads Nina off, while Maria confronts Jim and says that Nina and Torres are both gone. Two thugs attack Jim and he fights back, knocking them out. Maria invites Jim to look, and he draws a gun and tells him to tell him where Torres took Nina.

In the town of Alto Nuevo, the townspeople are preparing for Grant's arrival. Jim rides in and finds Artie talking to a woman. He draws his partner inside, and Artie says that Grant won't call off his tour plans because a "crackpot" is threatening his lie. Jim figures they have to find Torres because his plan might always be in motion. Jim spots Torres in a saloon's second-story window and points him out to Artie.

The two agents go into the saloon and buy drinks. Torres' aide Lopez asks Torres if he should take Nina to the cellar, and Torres tells Lopez to begin the entertainment early. The saloon girls begin swinging on swings above the patrons, throwing flowers, and the agents realize that one of them is Nina. Jim realizes that something is wrong with her, and Torres is playing games with them. While Jim carries Nina out, Artie tells the crowd that Jim is Nina's daughter and has been looking for her for years. Torres has Lopez take men to stop Jim, while Artie buys drinks for everyone to toast American fatherhood.

Jim takes Nina out in the alleyway, and she doesn't remember him. He figures that she's been hypnotized, and men attack him. Jim defeats them and runs into a nearby door

In the saloon, Lopez confronts Artie and tells him to go upstairs, with a hidden gun as additional persuasion. Artie has no choice but to go, to the upstairs room, and Torres seemingly hypnotizes Artie into believing they don't have enough proof to act. He tells Jim that when he returns to the Wanderer, he'll tell Jim that he's been exploring the dungeons beneath the saloon, and they should explore them. As Artie goes, Torres jabs a needle into Artie's shoulder, figuring he'll be insensate to pain. Artie doesn't react and Torres tells him to go.

At the Wanderer, Jim tells Artie that Nina disappeared during the fight. Artie explains that he faked immunity to the pain, and figures they should let themselves be caught. They go back to the saloon and enter the dungeons, break in, and hear running water. Torres and Lopez are there, and Torres says that it's an underwater river. Torres knocks out Jim and Lopez takes Artie down at gunpoint. He then chains up the two agents.

Later, Nina brings them drink and says that Torres doesn't know she's there. She gives them sips but says that Torres wouldn't like her helping them. Jim convinces her to take a pencil out of his lapel. They kiss, and Jim has her use the pencil's blowtorch feature to free him. Lopez is sleeping and wakes up when hears the explosions, and then the agents run through the tunnels with Nina but come to a dead end with a pool in the floor. Torres pumps in knock out gas to render them unconscious. Artie falls into the water and sinks out of sight, while Torres watches them through the window in a closed door.

That night, Torres strings Jim up in his saloon apartment behind a window, as Artie disguised as the President arrives in town. Torres aims two outside wireless rockets, one at "Grant", and one at the apartment, from a panel in the apartment. Torres says that he and the other men drew cards to stand guard that night, and insists that the other soldiers cheated. He explains that he plans to use one rocket to kill Grant and one to kill Jim. The people in the crowd set off fireworks, and Torres triggers the fuse on Grant rocket, tells Lope that there will be a one-minute delay, and Lopez should wait until the first rocket goes off and then join Torres in the tunnels.

Once Torres leaves, Jim tells Lopez that Torres is setting him up to eliminate any witnesses. Lopez finally panics and runs, and Jim swings himself over and kicks the control panel, knocking the Grant rocket off-course. The second rocket fires one minute early, as Torres planned, and Jim pulls himself up out of the way and lets the explosion bring down the rafter and free him. Artie sees the explosions, and watches as the off-course Grant rocket enters the apartment and finishes freeing Jim.

Lopez goes to the dungeons and confronts Torres. Torres has heard both explosions in the building, and realizes Grant still lives. He kills Lopez and then goes to the dead end. Jim is waiting behind the closed door. He closes the door but Torres forces it open with his superior strength. Torres refuses to flee and attacks Jim, who manages to throw Torres into the water. The former army man is too heavy to pull himself, refuses to take Jim's hand, and lets himself drown rather than face the indignity of hanging for his crimes. Artie runs in and removes his Grant disguise, and says that there's a tunnel leading to the river.

The next day, Grant arrives and gives his speech. Artie takes Torres' lamp to the Wanderer, and undoes Nina's hypnotism while Jim watches. She sees herself in the saloon girl outfit and assumes the agent took advantage of her, slaps Jim, and throws pillows and books at them in a fury. Jim throws things back as the Wanderer leaves.