I’m sure Constance Laughlin would not have wanted Marisa Hightower to take her murder personally. I mean, Ms. Laughlin had nothing against Ms. Hightower. It was simply a matter of mathematics. Remember Ms. Hightower’s scribbling on the back of her coaster? She figured the house and property she was about to inherit would be worth between two-and-a-half and three million dollars. Constance Laughlin did the same figuring: $2.5 million, minimum, divided by six (all the beneficiaries) equals $416,666.66. Minimum. It could well turn out to be half a million dollars! Would you kill for that? 

She did!

Constance Laughlin figured she would appear no more suspicious than any of the other suspects. Maybe even less so, since she had such a slight connection with the victim. Getting the poison wasn’t a problem; nor was lining a glass with it that she would eventually give to Ms. Hightower—along with a few drops of additional poison, just for good measure. She didn’t even have to kill her victim, just make her ill enough that she couldn’t attend the necessary meeting at Saundersfoot Castle to claim her inheritance. Whoops, she overdid it, and now the hostess flying in the skies is confined to a cage.