The Kind Worth Killing is your next choice in the "If you liked Gone Girl, you'll like..." progression. This novel includes all the requirements: Dueling narratives, despicable characters (that at times you can't help but root for), several twists, and a fantastic ending.
It's the story of a man named Ted, who has made millions in technology, and who strikes up conversation randomly (or is it?) with a woman named Lily at a bar at London Heathrow airport. They talk the whole flight home to Boston, and Ted reveals he's recently caught his wife Miranda cheating on him with a contractor building their McMansion on the coast of Maine. Ted decides, after several drinks, the best solution is to kill her. She doesn't deserve to live for what she's done to him. She is, indeed, the kind worth killing — a sentiment his new friend Lily wholeheartedly endorses, and therefore decides to help him plot to murder her.
Intermingled with Ted's tale is Lily's story as a teenage girl living in rural Connecticut with her hard-partying artsy parents — her dad is actually a famous novelist. When a pervert visiting artist named Chet does something gross to teenage Lily, she decides to get her revenge.
From there, much like Gone Girl, the less you know going in, the more fun your reading experience will be. Needless to say, the plot to kill Ted's wife doesn't exactly go as planned, and things get pretty crazy from there.
Often, Swanson reveals a plot point or engineers a twist, sometimes out of the blue, and at the time, it seems a bit off, or unearned, or just too random. (Through the first 100 pages, I kept thinking, "Why would Lily, a stranger, be so willing to help Ted kill his wife?") But one of the strengths of the novel is that then Swanson fills in the back story, and it makes sense...and is usually ingenious. You have to trust the writer here, and he'll reveal the reasons eventually. That's not always the case in thrillers — where sometimes, stuff just happens, and there is no good reason why. Here, there's always a reason — and it's why this is such a tightly spun, well-built thriller.
Another strength is the character Lily — she is such a sweet sociopath. Unlike Amy from Gone Girl, who we soon learn is pure evil, Lily maintains a semblance of rationality throughout. And that's why you find yourself continuing to root for her, even as she does awful things.
As we know, The Girl On The Train has been anointed the undisputed Next Gone Girl champion, and I liked that novel well enough. But I actually liked this one better. It's a helluva a ride, and highly recommended.