Suddenly

Suddenly is a 1954 American noir crime film starring Frank Sinatra and Sterling Hayden. In the film, Sinatra plays John Baron, the leader of a group of assassins who enter the Benson family's home to assess security risks before a presidential visit.
Once inside, Baron reveals himself to be a psychopathic assassin who kidnaps the family to use their home as a vantage point for his plot to kill the president. Sheriff Tod Shaw (Sterling Hayden) matches wits with the assassin and his gang in an attempt to save the day.