The Kids Who Knew Too Little (The League of Unexceptional Children, Bk.3)

Since being recruited by the League of Unexceptional Children, Jonathan Murray and Shelley Brown have rescued the vice president and stopped the outbreak of a virus capable of dimming human intelligence. Against all odds, these totally average spies have somehow managed to save the day...twice.

Now Jonathan's parents have been arrested by the CIA for treason, and liberating them means going head-to-head with a secret organization so powerful it has literally changed the course of history. It's Jonathan and Shelley's most dangerous mission yet, and one that will decide their fate as members of the League. Will they be able to accidentally sort of save the day one last time?