When a guardian angel – who invisibly watches over the citizens of Los Angeles – becomes captivated by a strong-willed heart surgeon, he ponders trading in his pure, otherworldly existence for a mortal life with his beloved. The couple embarks on a tender but forbidden romance spanning heaven and Earth.
As Christmas approaches, a department store worker whose life lacks fulfillment meets her guardian angel, who offers her a chance to change her circumstances by magically transporting her to Christmases past whenever she tries on a new pair of shoes.
A fateful night in 1959, four people die when the bus they are riding crashes. They continue as ghosts; their souls become eternally entwined to the life of a child born at the moment of their deaths as his guardians. Baby Thomas grows up to be a businessman who has memories of his playmates, but assumes they are products of his youthful imagination. When the ghosts realize they need Thomas' help to move on to the afterlife, they decide to make an appearance once more.