When a group of international criminals kidnap Dr. Rudy Wells in order to force him to build them a bionic man, Steve is sent to find and rescue him.

While scientist David Tate experiments in space with a serum designed to awaken cryogenically frozen patients, he is accidentally injected with too much serum. When the space capsule crashes, he begins terrorizing the countryside and Steve must hunt him down.

When the Prime Minister of a small country has a heart attack while negotiating a peace treaty with neighboring countries, she is selected to receive the first bionic heart. Steve is assigned to protect her while she is transported to the secret hospital where the procedure will take place.

When Steve discovers that there is another bionic man - Barney Hiller, a race car driver - he is assigned to help him adjust to his bionics.

Steve Austin buys a ranch in his hometown of Ojai, California. He reunites with childhood friend Jaime Sommers who is now a professional tennis player. They rekindle a brief childhood romance. Jaime Sommers is injured in a skydiving accident when her parachute collapses toward the end of a jump. Her right arm, right ear, and both legs are severely injured. With Jaime’s life in peril, Steve Austin persuades a reluctant Oscar Goldman to fit her with bionics. Although skeptical at first, Jaime Sommers quickly acclimates to her mechanized components. The bond deepens between the two bionic humans. Steve Austin proposes marriage to Jaime Sommers, and she accepts.

While Steve Austin and Jaime Sommers plan their wedding, Oscar Goldman submits his bill for making Jaime Sommers a bionic woman: She is to go on her first assignment with her fiancé to switch a flawed U.S. $20 bill printing plate for a perfect copy in the possession of a foreign counterfeiter named Joseph Ronaugh. Steve Austin vehemently objects, but Jaime Sommers acknowledges her debt and agrees. The two succeed in their mission despite a malfunction in Jaime Sommer’s bionic arm which nearly causes it to fail. It is soon discovered that her body is rejecting the bionics. Dr. Rudy Wells conducts an emergency surgery to no avail. Jaime Sommers dies.