Forced to take her stepsister Scarlett's place in a marriage pact between their grandfathers - a battlefield promise binding a Donovan to a mechanic's grandson - Claire Donovan trades her pride for access to her late mother's trust fund and weds Beau, a small-town car mechanic with a mute little son, Finn. Claire plans to endure one year, take the money, and leave; instead she finds herself defending Finn from bullies at his rehab center, exposing a cover-up that destroys her evidence and forces her son to apologize to his attacker. The quiet mechanic who steps in is not what he seems: Beau is the hidden heir of the Ashford Group, secretly appointed CEO, guarding his vineyard, his grieving son, and a truth he vows to reveal only when the time is right. As Finn calls his new mother Mom and Claire's guarded heart thaws, the Donovans summon them to a manor wedding - the same day as Scarlett's - where Grandpa plans a public announcement, and Beau must finally show her who he really is.
