Supergirl's Mehcad Brooks, who's played the show's version of Jimmy Olsen since the first episode, will leave during season 5. Jimmy Olsen is traditionally associated with Superman, but he was reinvented to become a part of Supergirl's world; Jimmy became a suave photographer, a seasoned adventurer, and even a potential love interest for Melissa Benoist's titular hero.
Jimmy's been on a fascinating path since his introduction, though; tired of standing by and watching other people save the world, he's suited up as DCTV's version of the Guardian. He worked the streets as a vigilante, striving to protect the people of National City from threats ranging from street crime to all-out alien invasions. Last season saw Jimmy injected with Harun-El, or Black Kryptonite, and as a result he briefly gained super-powers.
It seems Mehcad Brooks' time in the Arrowverse is coming to an end. EW has revealed that the actor is bowing out of The CW show this season, which means Jimmy will be leaving National City. Naturally, The CW is keeping quiet about just what's going to happen to Supergirl's best friend, but it sounds as though the door is being deliberately left open for him to return at a later date. "We love Mehcad and we’re sad to see him leave the show as a series regular," showrunners Robert Rovner and Jessica Queller said in an official statement. "He’ll always be a part of our Supergirl family and we look forward to James returning to National City at some point to visit his sister and his super friends."
Supergirl season 5 promises to be a uniquely challenging one for Jimmy Olsen. The Supergirl season 4 finale saw his lover Lena Luthor discover the truth about Supergirl's secret identity. She was left reeling and feeling betrayed by the people she's closest to, and most viewers expect Lena to lash out and become the villain of Supergirl season 5. Jimmy may well be the only one who can reach her.
Meanwhile, he'll also have to work out how to balance his life at CatCo with his vigilante career. Guardian's identity is no longer a secret, and in Supergirl season 4 Jimmy struggled to deal with the fact that his every move was being watched by the press. He's more used to being on the other side of the camera, and made a number of high-profile missteps that clearly troubled him.
All good things must come to an end, but the comment from Supergirl's showrunners does strongly suggest that Jimmy will leave a strong legacy behind. Last season introduced his sister Kelly, played by Azie Tesfai, who's been promoted to a season regular. It sounds as though the Olsen family will remain strongly connected to Supergirl.