New York Times bestselling author Kimberly McCreight delivers a tour de force of character-driven suspense: the story of two women whose secrets and desires entrap them in a deadly love triangle.

You had to rely on the power of love. That he loved you enough not to do the thing that would break your heart.

It was paper-thin ice on which to stake your survival.

Gretchen Falk, a Park Avenue sophisticate born into great wealth and blessed with a storybook marriage, knows she lives a charmed life, and she's not about to risk losing any part of it. That's why she tried to convince Richard, her devoted husband and father to their three children, not to join his old college friends on an expedition almost eight thousand miles away, to the imposing peak of Mount Kilimanjaro. Little did she know that the beautiful artist climbing alongside him might prove the far greater danger.

Frankie Callahan's dream of artistic success is within reach, with her career-making exhibition at a celebrated New York gallery only weeks away. If all goes well, the show will leave her financially independent, free of the tainted money that ties her to a past--and a man--she's desperate to escape. To mark the end of this chapter, she is going to climb Kilimanjaro. But when she learns she's the sole female accompanying a group of male friends, Frankie realizes that nothing about the trip will be as she expected. She certainly hasn't counted on meeting anyone like the very charismatic, very rich, very married Richard Falk. By the time the group descends--with one fewer than when they began--they have lost more than they ever could have imagined.

Now, just two weeks after returning to New York, Frankie is dead, her East Village loft a blood-soaked crime scene. When Richard is charged in Frankie's death, it falls to Gretchen to piece together how the life she so carefully constructed could have imploded so completely. There are only two things Gretchen knows for sure: she's the only woman Richard has ever loved, and he would never hurt anyone.

Someone Else's Husband is the sweeping and suspenseful story of two women on a collision course with love--and with each other--in which no one is right and everyone is very, very wrong.