Bingoed: An Essie Cobb Senior Sleuth Mystery

Why would spry senior Bob Weiderley suddenly faint and fall into a coma after winning a game of Bingo? After all, he was the most physically fit of all the men at the Happy Haven Assisted Living Facility (although there weren't many men at HH because women outnumbered them four to one). It was just very suspicious. That's why Essie Cobb and her friends and fellow residents--Opal, Marjorie, and Fay--decided to investigate. Was it possible that someone was out to get the friendly old gentlema...