What ho! You are Bertie Wooster, of London and points east, currently embedded for the weekend at Aunt Agatha's country pile, Heversham Hall. The tiara — Aunt A.'s pearl-and-emerald bauble — has been pinched from the wall safe in my bedroom, of all places, and the ball commences at eight.
The combination to the safe was known to four souls: Aunt A. herself, Sir Roderick Wattlesby (the trustee), Jeeves (the man of brains), and yours truly. Various other persons of doubtful reliability are scattered about the house. Click around. Question whomsoever. Examine whatsoever. Ring for Jeeves when stumped. When you've sorted out the cad responsible, push the Settle It button.
Tinkerty-tonk, and the best of British.