"Supergirl" Season 2 is currently in development but early images revealed James Olsen (Mehcad Brooks) transforming into Guardian. With his new indestructible suit, Guardian is expected to help Supergirl battle new criminals and supernatural enemies in the next story, although no longer as a sidekick.
Executive producer Andrew Kreisberg told TV Line that Olsen will decide that he cannot be a sidekick anymore, so he will be a vigilante instead. Olsen will morph into Guardian, who wears a powerful steel suit and mask, and carries a massive shield. Olsen's big change, however, will spell trouble in his relationship with Kara (Melissa Benoist) in "Supergirl" Season 2, because he will keep his new identity hidden from her. Kara may not be too fond of vigilantes in the first place, so the two are expected to clash soon. At the start of "Supergirl" Season 2, Kara and Olsen decided to remain friends although they had their romantic moments.
Furthermore, Guardian recruited Winn Schott (Jeremy Jordan) to help him in his missions. Winn will be providing Guardian with information from a safe spot and their relationship will offer some comedic relief in "Supergirl" Season 2. Kreisberg stated that in "Supergirl" Season 2, there will be a struggle between Kara and Olsen on who gets to become a superhero. In the meantime, Winn is working at the DEO and has to lie to everyone on how he is spending his nights because he is constantly supporting James.
Guardian was initially introduced by Jack Kirby and Joe Simon in the 1940s. The character, originally named Jim Harper in the comics, had no innate superpowers but wielded an indestructible golden shield. Harper had a blue suit and mainly relied on it as well as his own strength. It is still uncertain how Guardian will function in "Supergirl."
IGN reported that "Supergirl," which recently transferred to The CW, will introduce new characters in the second season, such as Superman (Tyler Hoechlin) and a female United States president (Lynda Carter). There will expectedly be new villains and threats as well, from Earth and outer space. "Supergirl" Season 2 airs on Mondays on The CW.