After the dissolution of her marriage, a writer is transformed into a "clam" via typo after her mother keeps texting her to "clam down." The funny if unhelpful command forces her to ask what it means to "clam down" during crises—to retreat, hide, close up, and stay silent. Idiomatically, we are said to "clam up" when we can't speak, and to "come out of our shell" when we reemerge, transformed.

In order to understand her path, the clam digs into examples of others who have also "succumbed to shellfish" to embrace lives of reclusiveness and extremity. But this is a story that radiates outward from the kernel of selfhood to family, society, and ecosystem. Finally, the writer must confront her own "clam genealogy" to interview her dad who disappeared for a decade to write a mysterious accounting software called Shell Computing. In learning about his past to better understand his decisions, she learns not only how to forgive him, but also how to move on from her own wounds of abandonment and insecurity.

Using a genre-defying structure and written in novelistic prose that draws from art, literature, and natural history, she unfolds a complex story of interspecies connectedness, in which humans learn lessons of adaptation and survival from their mollusk kin. While it makes sense in certain situations to retreat behind fortified walls, the choice to do so also exacts a price. What is the price of building up walls? How can one take them back down when they are no longer necessary?