Mikaela is a successful romance novelist who has had bad luck in love, visits a quaint bed and breakfast for a Christmas writer's retreat near a snowy lake town each year. Upon arriving, she meets dashing writer Levi, who soon convinces Mikaela that she shouldn't be writing about love, if she doesn't allow herself to get out and actually experience it.

Set during the height of World War II, Horizon centers on Lauren, a secretary at the FBI who begins a secretive investigation into files that have been stamped with the codename "horizon." The mysterious project provides links to the presumed death of her husband and the disappearance of a young girl.

The story of notorious outlaw Taylon Flynn, a man hell-bent on exiting this life in a blaze of glory. His plans go awry upon the discovery of the sordid life his estranged daughter is forced to live. To save her, he must summon the inner demons he purged long ago, and finds that redemption is a hard road to travel.