Campus Secret is the forty-second episode of Engine Sentai Go-Onger.
When Bin Banki starts mixing up recyclables into the regular trash, the Go-Ongers easily force him to run with them in pursuit. However, the Go-on Wings find Kegalesia has become a teacher at the nearby Todorokigaoka Private High School. Unable to get into the school, the two report to the Go-Ongers with Bomper suggesting one of them to pose as a student to get to the bottom of it.
Miu volunteers and goes undercover at the school as a shy girl to find where Kegalesia is. After searching through many school clubs, Miu runs into the prodigy Manabu Yushima, who becomes interested with her and attempts to use the Cupid's Arrow spell to make her love him. Revealed to be in possession of an item from the Braneworld known as the Magic World, Yushima runs off to his sole confident, Kegaleshia as the school nurse. After revealing herself, the Minister has Bin Banki get back the Mage's Wand and knocks Miu out to give to Yushima, who returns the favor by upgrading Bin Banki into Mahōbin Banki. As Mahōbin Banki uses his new magic powers to force the Go-ongers to attack each other against their will, Yushima attempts to make Miu his girl only to unable to with his magic. But after convincing him to use his true heart to win her love, Miu arrives with Yushima and the two strip Mahōbin Banki of his magical powers before Go-on Silver defeats him.
But when the Industrial Revolutionized Mahōbin Banki is overpowered by Engine-Oh G9, the combination is broken up by a mysterious figure with Go-on Red using Kyoretsu-Oh to scrap the Savage Machine Beast. Soon after, as Yushima accidentally destroyed his laptop and data he gathered of the magic spells, the Go-Ongers were curious about the mysterious sniper who attacked them.