When it comes to relationships, E.R. consultant Josh Sullivan is very happily single, and despite the attempts of the beautiful women he dates, he intends to stay that way. Single mom Dr. Kat O'Brien would usually be completely off-limits to him, except he can't get the stunning doctor out of his mind. And he's touched by her devotion to her six-year-old son, Archie, who he discovers is a pretty great kid. Before he knows it, Josh is hooked, but will Kat ever believe he can offer them a future?