|The first episode of the season basically sets up the concept for the rest of the series. Peter becomes invisible during a lab experiment, is recruited by the government, and travels around the world helping people.|
The only major change in the storyline is in "Picnic With Death" when Peter's existence as an Invisible Man becomes public knowledge after a car accident. Once his condition becomes public knowledge, he usually ends up choosing who to help and often becomes involved in private matters where his unique talents can prove of use.
The season has more of a family feel to it, with Diane and Sally regularly becoming involved in Peter's mostly domestic adventures. Diane is in 11 of the 13 episodes, and Sally is in 7. The only other recurring character is Peter's nominal superior, Sir Charles. He appears in 4 episodes this season,. In Season 2, the actor playing him appears as a different role, and a different actor plays the character in the series finale.
Behind the scenes, several actors play the role of Peter Brady. After episode 4, the producers settle on Tim Turner to play the role for the rest of the series.