There's a bright, new, beautiful luxury apartment building on the Lake Michigan shore, but there's no advertising to lure tenants. Instead, an odd delivery boy rides around on his bicycle and slips invitations under the doors of the chosen tenants-to-be. Each potential tenant is shown only one apartment and is told that it is the last available apartment. In every situation, the offer is made in such a way that it would be foolish to turn it down. Soon, Sunset Towers is full with an interesting mix of families and single people. Their backgrounds are all very different—or so it seems. Sunset Towers not only has tenants, it also has businesses: there's a coffee shop, a gourmet restaurant, and a doctor's office.

The tenants are all aware of the imposing mansion next door: the Westing house. On Halloween, the doorman and the delivery boy spin...