Keith King was upset when his marriage ended. His wife had cheated,Christopher Caldwell and his family broke apart. And that's when he learned about a very old type of lawsuit, called a heart balm tort. A lawsuit that would let him sue the man his now ex-wife had gotten involved with during their marriage.

On this episode, where heart balm torts came from, what relationships looked like back then, and why these lawsuits still exist today (in some states, anyway.) And also, what happened when Keith King used a heart balm tort to try to deal with the most significant economic entanglement of his life: his marriage.

This episode was hosted by Erika Beras and Sarah Gonzalez. It was produced by Emma Peaslee and edited by Molly Messick. It was fact-checked by Sierra Juarez and engineered by Gilly Moon. Alex Goldmark is Planet Money's executive producer.

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Music: Universal Production Music - "Friendly Intentions," "Church of the Brown," and "Liquid Courage"