My Sister Is Going to Kill Me: A Novel

by Nina Simon

From the New York Times bestselling author of the runaway hit Mother-Daughter Murder Night, a Reese’s Book Club pick, comes another fun, family-centered whodunnit about two sisters who work together to find a killer as they raft down the rapids of the Grand Canyon. What's a family vacation without a little murder? Liv and Mandy Chisholm’s yearly sister trip is a sacred tradition, an attempt to bond as their lives increasingly diverge. Liv, the ever-practical older sister, packs the color-coded itineraries. Mandy, a bedazzled human tumbleweed, brings the spontaneity. This year, the sisters take off for a rafting adventure through the breathtaking depths of the Grand Canyon with a group of strangers. But beyond the terrors of whitewater rapids, sibling squabbles, and rogue reptiles, the ferocious beauty of the river carries a darker undercurrent, and an unexpected a murderer in their midst. When a fellow traveler is found dead and another corpse hits the water, the rafting trip flips from idyllic sister vacation to high-stakes murder investigation. Every suspect has a secret, every clue is drenched in mystery, and Liv and Mandy can hardly trust each other, let alone their own instincts. With the river raging and danger around every bend, the Chisholm sisters must work together to catch a killer—and keep their relationship from capsizing—before it’s too late.

Genres: Mystery

Audible Audio

Expected publication August 18, 2026

About the author

I write crime stories about strong women.

My newest novel, MY SISTER IS GOING TO KILL ME, will be released in August 2026. It is a fun, twisty mystery about two mismatched sisters who must catch a murderer as they barrel down the Grand Canyon on a whitewater rafting trip.

My first novel, MOTHER-DAUGHTER MURDER NIGHT, is a New York Times bestselling mystery about a grandma, single mom, and teenage girl who come together to solve the murder of a naturalist who washes up in the Monterey Bay.

Writing has always been my joy. In college, I was an electrical engineering student by day and a slam poet by night. After a brief stint at NASA, I started designing interactive exhibits and eventually became a museum director. I wrote two books of nonfiction about creating participatory, relevant cultural institutions.

Then, my mom got sick. I quit museum work to care for her, and I found myself turning to fiction, and mysteries, as a way to escape and find pleasure during a hard time. I wrote my first novel by my mom's side, featuring a detective/hero based on her. Now, my mom is doing better, and I'm gratefully spending my days writing, reading, and cherishing the people in my life.

I live off-the-grid in the Santa Cruz mountains. You can find out more about me at https://ninaksimon.com/

I write a very occasional newsletter at https://ninaksimon.substack.com/

Reviews

[Kathy · Rating 5 out of 5]

Great read. Now I want to go rafting in the Grand Canyon..maybe. Good characters. Perfect setting. Recommend.