Vince Larkin is the secondary protagonist in the film Con Air. He works as a member of the U.S. Marshals Service and oversees the transfer of prisoners aboard the prison plane the "Jailbird." When the plane is hijacked, Larkin struggles to remedy the situation and learns that a parolee named Cameron Poe is aboard, trying to stop the prisoners from escaping. He is firm, but fair and vigilant in his performance as a marshal officer and does not let personal feeling interfere with duty and procedure. When faced with a new situation, he remains calm and keeps a sensible attitude in the face of opposition. Larkin is portrayed by John Cusack.
Larkin first appears arriving at Vacaville, CA, for a transfer of various prisoners, most of whom are among the most dangerous criminals on record. He appears wearing a khaki-colored suit and open sandals. While his associate Skip Devers briefs the guards on procedure, Larkin silently mouths some words of conduct. Both then meet with DEA agent Duncan Malloy and his partner Willie Sims, present for the custody of drug cartel leader Francisco Cindino, awaiting transfer in Carson City, NV. Larkin introduces Sims to various separatees, including Billy Bedlam, Nathan Jones aka "Diamond Dog", and Cyrus "The Virus" Grissom. Larkin also identifies Cameron Poe, an honorably discharged U.S. Army Ranger on parole after involuntarily killing an individual.
The Jailbird is soon taken over by the prisoners, having escaped from their cells and capturing the guards aboard. Larkin is called to Grissom's former holding cell, where he discovers numerous concealed items, including a schematic of the Jailbird and cryptic documents that reveal a rendezvous at Carson City. Larkin leaves the cell, which saves him from being killed by a bomb hidden among Grissom's possessions. Malloy is furious with Larkin's supposed incompetence and demands a solution be found.
Larkin soon contacts the Jailbird, having escaped from Carson City, demanding to know where the plane is heading. Grissom simply mocks Larkin, unaware of Poe having heard much of the conversation. Larkin then summons Poe's wife Tricia and daughter Casey to question Poe's reasons for staying aboard. He is unable to provide a solution for stopping the plane, against Malloy's wish to simply shoot it down. When Malloy and Devers leave in attack helicopters to chase after the Jailbird, Larkin meets Tricia and Casey, and shares their belief that Poe has a sensible reason to stay aboard. He is then contacted by Fresno police, having found Pinball's body dropped from the plane, informing Larkin of the plane's destination for Lerner Airfield, the transponder removed and placed on another plane flying to Arizona. Larkin's attempts to persuade Malloy to abandon the false trail are unsuccessful. He "borrows" Malloy's car to drive to Lerner Airfield, requesting police and SWAT Team assistance along the way.
Arriving in Lerner before the plane, Larkin finds the control tower operator dead (possibly murdered by Cindino's associates) and soon meets Poe after discovering a planned betrayal by Cindino to leave the other prisoners behind. Poe doesn't trust Larkin, but agrees to help him stop the prisoners in his own fashion. Larkin prevents Cindino from escaping by dropping a crane on top of his plane, damaging it beyond takeoff ability, quickly hiding to avoid being noticed by the other prisoners.
When the SWAT Team arrive, Larkin notices them walking into a trap and orders a fallback, but it is too late. The prisoners and SWAT Team exchange fire, the latter being slaughtered, until Larkin uses an old bulldozer as a shield, giving the SWATs an advantage. Defeated, the remaining prisoners leave in the Jailbird just as Malloy arrives to see his car severely wrecked. Larkin appears mildly amused by Malloy's furious outburst and then joins the pursuit of the Jailbird.
Larkin orders Malloy to not fire upon the plane, giving Poe enough time to take control and force a landing in Las Vegas. Larkin arranges for police and ambulance crew to be ready for when the plane stops and is present for the recapturing of surviving prisoners. When Grissom, Diamond Dog and Swamp Thing escape on a fire truck, Larkin joins Poe in a motorcycle chase through the city, dodging bullets and the truck's water hose being used by Grissom. With Diamond Dog killed by Poe and Grissom chained to the ladder, Larkin uses an axe to chop through where Swamp Thing is driving. He uses a hose to flood the compartment, causing the truck to crash, killing Swamp Thing.
Poe shakes Larkin's hand, saying that he trusts him now. Larkin then apologizes to Malloy for stealing his car, offering to have it repaired, but Malloy gently declines. The film closes as Larkin then looks on to see Poe reunited with his wife and daughter.