Nora O'Brien leaves Ireland to visit her brother in America. On the trip she suffers a concussion, and soon is mistaken for another Irish girl named Nora who is on her way to visit her aunt in the US, Mrs. Watson, who has not seen her niece in many years. Nora, still somewhat dazed from her injury, is taken to the Watsons' home, and when Mrs. Watson's son Jack returns from college, he falls in love with her but cannot express it to her because he believes she is his cousin. Complications ensue.