Since its debut in 1990, "Home Alone" has become as much a part of the Christmas cinematic ritual as "It's a Wonderful Life."

But unlike that uplifting tale about the good of mankind, "Home Alone" tells a rather unsettling Christmas story of a precocious 8-year-old who, accidentally abandoned by his family, is forced to defend his home from two dimwitted burglars.

Kevin McCallister (Macaulay Culkin) turns his family's home into a veritable funhouse of torturous booby traps that so-called Wet Bandits Marv (Daniel Stern) and Harry (Joe Pesci) hilariously stumble through, and the transformation of a suburban Chicago home into a relentless injury machine is nothing short of spectacular.

But it does require quite a suspension of disbelief.

Can a man really be hit square in the face with a steam iron and walk away unfazed? What kind of permanent physical damage would a blow torch to the head really do?

To answer these questions and officially dissolve "Home Alone"'s Hollywood magic, I spoke with my friend Dr. Ryan St. Clair of the Weill Cornell Medical College. Enjoy.