Macy’s Department Store in New York City needs a replacement Santa and hires Kris Kringle, an old man who has been living in a retirement home. His effect on the customers astonishes his employers, especially Doris Walker, the hard-working personnel manager. Not everyone, however, perceives Kris as gentle and well-meaning. Macy’s vocational counselor and self-appointed psychologist, considers Kris to be deluded and dangerous and has Kris committed to Bellevue Psychiatric Hospital. 

There Kris awaits a competency hearing. His only hope of escape lies with a help of a young lawyer named Fred Gailey, Doris Walker’s neighbor. Fred is in love with the cynical Doris and wants nothing more than to marry her and be the father her daughter Susan needs. But convincing Doris he is worthy of her love is not easy; in fact, it’s almost as difficult as the new challenge he faces in court ... convincing the judge, and all the world, that Santa Claus really does exist. But Fred has Kris Kringle on his side, as well as the United States Postal Service, and with a little help he is able to pull off a true Christmas Miracle.