When the book opens, a bunch of people are headed off to this deserted island to see someone they barely know. If that sounds like a stupid idea to you, don’t worry—we thought so too. After all, this is pretty much the classic horror movie moment where you shout at the characters, “Stop poking around in big abandoned houses, you idiots! No good comes of this!”
But of course, all ten characters go off to the big deserted island and end up in a mansion where they’re told by the butler and cook that their host will be joining them later. In the meantime, they get to eat and drink on the house, so they’re all pretty happy. That is, until a big booming voice comes on over the gramophone (this old-school device for all you young whippersnappers) accusing all ten guests of committing murders.
Oh my! The plot thickens.
Everyone’s very shaken up, and they get even more agitated when Anthony Marston, who is accused of causing an automobile accident, takes a drink and promptly dies. (How’s that for an effective anti-alcohol campaign?) They think that perhaps he committed suicide out of sheer guilt, and everyone goes to bed feeling uneasy—but probably not as uneasy as the cook, Mrs. Rogers, who winds up dead as a doorknob next morning.
Now everyone’s really getting nervous, and they trot off on a detailed search of the island. The search turns up nada, which means—fire up the logic engines—that one of them must be the person who’s killing off everyone. The third death of General Macarthur confirms this hypothesis. Soon, they’re all running about, being very suspicious of each other and trying to solve the mystery before the clock runs out slash anyone else winds up dead. To make things creepier (and more stressful), every time someone dies, one of the ten soldier figurines in the room goes missing.
Can you see where this is going? Dun dun dun.
Mr. Rogers dies the next morning when he’s cutting wood, and then Emily Brent dies soon after from a hypodermic needle injection (meant to signify the bee sting in the nursery rhyme). Next up comes Justice Wargrave, shot through the head while regaled in judge’s robes.
Everyone is naturally freaked out and that night, Blore, Vera, and Lombard notice that Dr. Armstrong isn’t in his room where he’s supposed to be. Their deduction: he must be the killer! Unfortunately, a thorough search fails to turn him up, and Blore dies when he goes back into the house and is hit on the head by a marble clock that is shaped like a bear. (Okay, now that’s just funny.)
This leaves just Vera and Philip, who are both convinced that the perpetrator must be the missing Dr. Armstrong, right? Nah, way too easy. Instead, they find Dr. Armstrong’s bloated body and realize that he must have drowned. That leave just two of them, which... uh-oh. It must be either Vera or Philip, right? Vera manages to sneak the revolver away from Philip and shoots him, but turns out she’s not the killer, either.
Well, actually she is a killer: turns out, the big announcement at the beginning of the house party accused her of letting a little boy drown when she was governess. Consumed by guilt, Vera heads back into the house and hangs herself. Final count: ten dead bodies on Soldier Island and no explanation as to who killed them.
But keep on readin’, because now we come to the epilogue, which introduces us to some seriously confused police. No one could have gotten on or off the island, plus the chair that Vera kicked in order to hang herself wasn’t found kicked over which means that someone had to have put it back in its place after she died. Luckily for our poor investigators, a bottle with a letter inside ends up washing onshore some time later.
In it is a detailed confession by (spoiler alert) Lawrence Wargrave, who admits that he always liked killing things and seeing them suffer, but his extreme sense of justice won’t allow him to be a murderer. Instead, it allows him to become a judge! (Yeah, seems weird to us, too.) Anyway, he became obsessed with the idea of bringing justice to those who have escaped the law—like victims for the Soldier Island scheme. Oh, and you’ve probably guess that he didn’t really die after Emily Brent did—in fact, he was alive the whole time. But not for long. He’s killed himself by rigging up the revolver to a piece of elastic and shooting himself in the head. That way when his body is found, it will still looks like he died after Emily Brent.
So why go to all the trouble of sending off this message in a bottle. So his brilliance can be known, obvs. Um, noted?