Once Upon a Broken Heart features Evangeline Fox, who has always believed in true love and its associated happy endings, only to have her heart shattered when she learns that her beloved plans to marry someone else. In a desperate bid to prevent the wedding, she strikes a bargain with the enigmatic and cunning Prince of Hearts, who demands three mysteriously timed kisses as payment. However, she soon discovers that dealings with the immortal prince come with high stakes, thrusting her into a perilous game of love and deceit that could culminate in the most joyous of endings or the most devastating of tragedies.