After Lyn (Anne Bancroft) dumps him, Jed (Richard Widmark) sulks until he spots gorgeous Nell Forbes (Marilyn Monroe), who recently moved to New York City. But Jed soon realizes that Nell harbors a dark past when her mental instability becomes apparent. While she babysits the daughter (Donna Corcoran) of Ruth (Lurene Tuttle) and Peter (Jim Backus), Nell's sad truth can't be hidden -- not even by her Uncle Eddie (Elisha Cook Jr.).