XxxHOLiC the Movie: A Midsummer Night's Dream

At a mysterious auction in an old mansion, collectors vanish one by one as the night unfolds. Yuko and Watanuki must discover the mansion's owner and the true nature of what's being sold before it's too late. Yuko receives an invitation for the opening of an auction from a mysterious unknown sender. Likewise, fanatical collectors are summoned to an old mansion whose owner doesn't make an appearance. One after another, each collector disappears and a number of other strange occurrences happen during the night. The questions of what exactly it is that's being auctioned and who the owner of the mansion is must be solved in order for Yuko and Watanuki to get to the bottom of this. —Anonymous