After Alex wins a scholarship to Oxford University in London, the Keaton family makes an entire vacation out of it. However, a mysterious man on the plane ride to London plants a brush in Elyse's bag that containing top-secret microfilm. The Keatons are completely oblivious to what the brush contains, but after unexpected things keep happening to them, they start to realize that it might not be just a coincidence. After arriving at Oxford, Alex struggles with tough classes and even tougher classmates, Mallory finds romance, and Elyse and Steven get embroiled in international espionage.