Eccentric Jeffrey Mannus is 29-years-old and still lives at home with his angelic mom, Jan. He sees no reason to alter this arrangement, but his perfect world is upended when Jan meets Mert, a motivational speaker. Mert successfully woos Jan and moves in on Jeffrey's territory, something Jeffrey will not tolerate. Jeffrey enlists the aid of an unlikely ally, an aspiring singer-songwriter, Nora, with an anti-establishment penchant and a soft spot for him. As the war between Mert and Jeffrey escalates, something unprecedented happens--slowly, to both his own surprise and horror, Jeffrey discovers his inner adult.