''The Sweepstake Murders'' begins at the conclusion of a casual bridge party, where nine men form a small syndicate-dubbed the "Novem Syndicate"-to buy tickets for a coming sweepstake on the Epsom Derby. They casually agree to pool any potential winnings and divide them among the living members.
Against all odds, the syndicate wins a massive fortune of £241,920 (equivalent to tens of millions of dollars today). However, before the prize money can be collected, one of the members dies under highly suspicious circumstances. Because of their hasty agreement, the deceased man's share is split among the surviving members-exponentially increasing the payout for everyone else. As more members begin to die one by one, a deadly game of subtraction begins, leaving Sir Clinton Driffield to decipher who is systematically killing for profit within a closed circle of suspects.
