When Brady's friend tries to perfect his fuel diffuser, four pilots are killed in test flights; Brady intervenes to determine if sabotage is involved.
Peter must travel to Amsterdam to help recover a file that a spy stole after killing a British professor.
At an awards ceremony, Peter must rescue a Soviet writer being held for speaking out against her repressive government.
An important scientist decides to walk away from his groundbreaking research as he makes a critical discovery; Brady must find him and convince him to return to his work before foreign agents steal his secrets.
An American woman in London seeks Peter's help in rescuing her twin sister, who was kidnapped from her hotel after witnessing a murder.
An invisible rabbit sends Peter to a French chateau where invisibility experiments are being conducted.
While looking into an international drug ring, Peter's identity is stolen and used to transport drugs across the border.
Terrorists gun down a family in an Italian market, sparking an investigation into how the guns are acquired; Brady must break up the gunrunning activity.
Peter helps a professor who inherited the throne of a Middle Eastern nation after his brother's assassination.
Peter jumps into action when he finds out that an agent with gambling debts has sold information about a new rocket to the enemy.
Brady provides help to a friend that gets trapped in a cave-in with a bomb that will detonate if a shadow hits it.
A plane crash reveals that a canister of uranium was being smuggled into England as part of a pacifist's plan to initiate world peace.
While working in the lab, scientist Peter Brady gets exposed to a radiation leak and becomes invisible; the British government wants to classify him as top secret and lock him up, but he escapes.
Peter must parachute into an unstable Middle Eastern country to rescue an intelligence agent who is being held captive.
A disfigured tycoon tells Peter he wants to become invisible, but his motives have political implications.
A car accident leads to Peter's existence being revealed to the public; Sally's friend uncovers her stepfather's murderous plot.
Peter's vacation is interrupted when someone breaks into an atomic research station and smuggles vital secrets out of the country.
Hoping to regain his physical form, Peter Brady teams up with an Iron Curtain scientist who has been working on invisibility.
After agreeing to help a foreign refugees organization, Peter Brady is caught in an elaborate scheme to capture the Invisible Man.
An actress becomes the target of a blackmailer after accidentally causing the death of a homeless man.
Peter helps a blind woman clear the name of her pilot husband when he is framed for smuggling heroin.
An innocent man who was jailed for a crime he didn't commit breaks free and searches for a key witness.
A group of thugs in Italy kidnap a professor who is vital to the invisibility project and forces him to develop a numerical system to win at roulette.
A stolen briefcase leads Brady to the abode of a gold magnate who really wants his partner to be killed.