From the piddling kid stuff of their first cases, the McGurk detective organization has been getting into ever heavier crime, revving up the action without losing their kids' appeal as play-acting amateurs. This episode begins as usual in the organization's basement headquarters, with leader McGurk assigning the other kids to promotional-exam fieldwork. It ends in the parking lot where the gang foils a million-dollar kidnapping. There's some friction right at the start when Wands, the organization's only girl member, brings her visiting Japanese pen pal Mari to a meeting and McGurk won't let her stay. But Mari does better than any of the regulars in the fieldwork exercises, such as noting examples of suspicious behavior. Member Brains Bellingham, for his part, overhears what sounds like a plot to heist a million dollars worth of jewelery at the upcoming senior citizens' picnic, where Wands will be helping serve and Marl will be performing. So the organization's four boys gain entry to the picnic, only to discover that Maxi herself is the million-dollar target. It's neat how all those earlier examples of suspicious behavior mesh, in retrospect, with the kidnapping plot--and how Mari gains her full-fledged organization membership. Nimble work as usual.