Haven is based on the book "The Colorado Kid" by Stephen King.
It follows FBI agent Audrey Parker (Emily Rose), who arrives in the small town of Haven, Maine to solve the murder of a local ex-con. She then learns a whole lot more about this unusual enclave. She quickly settles in with the local sheriff, Nathan Wuornos (Lucas Bryant) and town ne'er do well, establishment owner and boat dweller Duke Crocker (Eric Balfour). She comes into contact with a lot of strange inhabitants of Haven including local brothers and owners of the Haven Herald, Vince Teagues (Richard Donat) and Dave Teagues (John Dunsworth).
Haven is plagued by "Troubles" that only occur once every 27 years ... along with different incarnations of a woman who looks a heck of a lot like Audrey Parker. Imagine everyone's surprise when an FBI agent arrives in town also bearing the name of Audrey Parker. If she's Audrey, then who is the gal who has been masquerading as Audrey? The answer turns out to be much longer and more difficult to believe than even the Troubles themselves.
Characters come and characters go, but the five main players have been consistent throughout the five seasons.