<p><strong>Best of Enemies Worst of Allies—and Now the Killer is After <em>Them</em>! </strong></p><br /><p>When the notorious author of sure-to-be scandalous <em>roman à clef</em> is shot dead by an invisible assailant during a signing at Concord’s staid and stately Marlborough Bookstore it falls—for reasons still hard to explain—to feuding mystery authors Felix Day and Leonard Fuller to solve a real life murder.  </p><br /><p>Despite the fact that they’re technically both suspects it’s the perfect opportunity for Felix and Len to match wits and sleuthing skills. But while they’re busy trying to outsmart (and impress) each other a ruthless murderer is closing in on our two intrepid investigators…</p>