On an airfield outside New York City, a man named Dick Benson gets onto a plane with his wife Alice and daughter Alicia. Initially, they are denied passage, but Benson insists, claiming his wife's mother is sick and they must get to her. As they board, a man reaches into his coat, asking his friend if he should shoot him. He friend says they'll handle it in the air.
The plane takes off and the passengers mingle. Alice Benson chats with a man named Arthur Hickok, who when he meets Dick Benson, recognizes him as an explorer and adventurer. Benson goes to the washroom and when he returns he finds Hickok, Alice and Alicia gone. When he questions the other passengers, the men, now obviously gangsters, say no one was ever sitting there. Benson threatens them and a fight ensues. Benson, no stranger to hand-to-hand, starts to get the upper hand until hit from behind with a fire extinguisher.
Three weeks later, Benson wakes up in a hospital, where his doctor explains he's undergone a tremendous shock. Handed a mirror, Benson sees his facial features are almost paralyzed and his hair, skin and the irises of his eyes have turned completely white. Against his doctor's advice, Benson leaves the hospital and returns to his penthouse apartment. There, he breaks out his old exploring/adventuring tools: guns and knives.
Benson returns to the airport and discovers the plane he rode in has just been given a new coat of paint. As he continues to investigate, he is jumped by an extremely strong, extremely well-spoken giant of a man. With his superior speed and combat skills, Benson defeats the man, who thinks he is about to be arrested. Instead, Benson introduces himself and the man, Algernon Heathcote Smith, recognizes him. Smith, who goes by Smitty, says he is a doctor of Physics, framed and wanted by the police, forced to do unskilled labor at the airfield. He shows Benson the plane contains a trapdoor, which may have concealed his wife and daughter.
At that moment, thugs arrive with guns. Smitty takes one out by throwing a chair at him and Benson shoots the other, purposefully grazing him in the head. Smitty and Benson realize they're a team, and Benson sends Smitty into the city for greasepaint while he searches the plane, finding a map with an X marking the spot where his family vanished. Is is an island he asks Smitty to investigate. Benson uses the greasepaint to color his face normally and he pushes his facial features into the disguise of an old man.
Benson boards the plane as the old man and is joined by an old woman named Van Dunce. Over Lake Ontario, the gangsters give Van Dunce a parachute and push her off the plane. Benson is not provided a parachute, but he is pushed off the plane, too. Showing remarkable foresight, Benson has hidden a parachute on his person and he glides to the ground.
Mrs. Van Dunce joins a group of people held prisoner on the island by the mobsters. The group consists of the majority stockholders of the Acme Motor Company. The mobsters demand the company be signed over to them. Mrs. Van Dunce refuses and is threatened with death. Benson steps from the shadows and a gunfight breaks out. Benson takes down four criminals with well-aimed shots, but more criminals converge. Out of bullets, Benson kills another man with his knife. The last man threatens Benson with a gun, giving Smitty time to come out of the shadows and knock him unconscious. Smitty says he's discovered the owner of the island. Benson says he's already figured it out. He demands that man come out of the shadows where he's been watching.
Arthur Hickok, the man Benson met on the plane, steps forward. Benson explains he knew Hickok was the mastermind since he was kidnapped but was not with the other prisoners. Answering Hickok's question of what happens next, Benson wraps his hands around Hickok's throat. Smitty pulls Benson away, unwilling to see revenge exacted with murder. His mission to avenge his family complete, Smitty asks what Benson will do next. Benson answers he intends to launch a crusade against injustice and becomes the Avenger.