On an autumn evening in New York, Billie West is rocked by the cries of her best friend Cassie Barnwell, whose baby has been kidnapped. Amid the chaos, Billie is hit with the appalling realization that she played a role in this horrifying act. Once childhood confidantes, now estranged, Billie and Cassie's divergent paths in life have created a chasm. Cassie, living in affluence and recently embracing motherhood, strives to erase her history including Billie, who lingers on the fringes, childless and incompatible with Cassie's polished existence. Despite their differences, Billie is privy to Cassie's darkest misdeed and is driven to mend their fractured bond. 'Bye, Baby' is a narrative told through their alternating voices, dissecting the complex terrain of female friendships, the scars from past wounds, and the intense demands that women face in their personal connections.