The teenage girl wrapped in a sheet calls herself Casper (as in "The Friendly Ghost"). But Secret Master of Fandom and private detective Spade doesn't find her friendly, and she's definitely not a ghost. Still, Paladin demands that Spade babysit Casper, and Spade never says no to Paladin. Even when it comes to babysitting on Halloween weekend, while Spade runs the second most important convention of the year. Because Paladin doesn't ask favors; she solves crimes. And apparently, she—and Casper—need help only Spade can provide.