The answer to this question can be found in the closing moments of chapter 10. Near the beginning of this chapter, Kevin comes over to Max and announces that he has a quest for the two of them. Max isn't super thrilled about it, but the prospect of finding a treasure that Kevin knows the location of wins out. The two boys then prepare themselves to go out late at night. They try to darken their faces and are sure to wear dark clothes. Kevin's night raiding outfit is a Darth Vader costume. The two boys wait until about three o'clock in the morning before going out to seek the treasure that Kevin knows about.
It turns out that Kevin saw some thugs throw something into a storm drain. Max pulls the grate off, and together, Kevin and Max fish out the "treasure." The item turns out to be a disgusting purse, and Max isn't hopeful that it will contain anything worthwhile. Kevin opens the purse, and he finds that the purse has a wallet inside of it. The wallet contains no money, but it does still have the owner's ID. It turns out that the wallet and purse belong to Loretta Lee. Kevin believes that she is a "damsel in distress," but Max ends the chapter by ominously telling readers that Lee is a "damsel who causes distress."