Riley, Manny, and Ginni Burriss have all joined S.I.S.A, following their parents' footsteps. With the threat of T.E.A.L increasing, the siblings must figure out a way to stop them.
When S.H.I.E.L.D. runs into a new team of enemies to tough for them to handle, Phil Coulson discovers another agency known as the O.S.S. The agency has a group of Spy Kids who go undercover, going where adult spies couldn't go, and doing what adult spies couldn't do.