It's graduation time, but just as the ceremony gets underway, the entire class mysteriously blacks out. When they wake up, they're not sure what happened. The girls eventually discover that Chet wants to force everyone to stay in high school forever.

Sam, Clover and Alex arrive at Malibu University. However, because they enrolled at the last minute, they find themselves in a bit of a housing dilemma.

The girls' professor picks them to play the role of infiltrators in a class exercise recreating a famous espionage event from the past.

Jerry asks the girls to transport an extremely dangerous criminal, an 80-something, grandmother. She immediately begins sweet-talking them. With the girls' defences down, she makes her move.

With Blaine now officially Clover's boyfriend, she's happier than ever. Though all is well in the relationship department, Clover's spy life isn't running so smoothly.

When Clover is accused of plagiarising and stealing, she starts to think it's no coincidence. She discovers that her old nemesis Geraldine is behind it all and that she has captured Blaine.