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Elsa looked up. “But if that guy on the deck killed Manfred, why did he do it? What was his motive?”
“Professor Drake — he’s an adjunct professor, really — was Kim’s lover. And Kim was Manfred’s accomplice — responsible for all the weird footprints and Latin writing and spooky stuff, here and in other places. She thought her association with Manfred was going to make her a lot of money (that’s a long story) but I don’t know if they were lovers. For the purposes of this explanation, it doesn’t matter.” She looked at the sheriff. “You’ll have to look into this, but I believe Professor Drake found out about Kim’s affiliation with Manfred, and he assumed that his lover was two-timing him.”
“We’ve seen some of his letters to Kim,” Rhonda put in, “and… well, they are love letters, but they do sound like he was pretty serious about her.”
“I expect you’ll find that he was distressed to discover that his young girlfriend was attached to a shabby middle-aged con man. And he decided to remove that part of the triangle.”
“But Kim always told us that her professor was married,” Becky pointed out. “That’s why he could never come over. He had to hide their relationship from his wife. And of course it could mess up his career.”
My employer nodded. “It’s true — he is married. I have sources, and friends, on campus, and it was fairly easy to figure out which professor was Kim’s lover. When I started to investigate Professor Drake, I found out about his wife, and I also learned that he has a sailboat, and a small rowboat. Which made me think that Manfred was never on the island on the night he died. Professor Drake killed him, and then transported him to the island, probably in his rowboat, and dumped his body on the beach below this house, probably as a message to Kim.”
“But then why did he come back the next night, dressed like Manfred, and kill Mary? That makes no sense,” Li protested.
“That would make no sense, I agree. And that’s not what happened. Kim killed Mary, as she confessed to Marshall and Miss Peabody, because she blamed Mary for Manfred’s death. Professor Drake was going to show up and freak Kim out — he may have thought that her professed belief in the supernatural was sincere — to get back at her for betraying him with Manfred.”
“Of course,” Jo said slowly, “Professor Drake was married, so him feeling betrayed by Kim’s ‘infidelity'” — she stuck her hands out from under her quilt for a second to make finger quotes — “was hypocrisy. Definitely.” I could tell that she was making a mental note of this, filing it away for her own writerly purposes.
My employer nodded. “Hypocritical, yes, but, from his point of view, understandable. But imagine his surprise upon ascending to the deck here, in his Manfred disguise, and finding a dead body. That was certainly not part of his plan. And then he heard Kim scream, because she’d seen a ghost in the middle of her crime scene, which was certainly not part of her plan. It’s no wonder he got out of here quickly at that point, relying on the fact that nobody likes to use those stairs to the beach. Let alone climbing down them in pursuit of a dead man.”
“But then why did he come back tonight? Kim’s not even here — she’s in jail.”
Rhonda shrugged. “We haven’t released that information to the press. He probably doesn’t know.”