Grojband follows the story of a Canadian indie rock garage band of the same name formed by Corey Riffin and his three best friends, Laney and twin brothers Kin and Kon, as they work together to propel their band to international stardom. When they do not have the lyrics, Corey and his friends get Trina, Corey's sister, into an emotional mode to write entries in her diary that Corey can use for lyrical inspiration, so that Corey and his friends can perform a perfect song.