The Wolf at the DoorBy: Jack Higgins Series: Sean Dillon Jack Higgins doesnt stint on action (Publishers Weekly) in this New York Times bestseller featuring black ops specialist Sean Dillon. On a Long Island pier, a trusted operative for the President is wounded by gunfire. In London, an adviser to the Prime Minister approaches his car when it explodes. In New York, British soldier turned covert operative Sean Dillon is approached by a man with a pistol in his hand