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This December, Tom Cruise steps into the shoes of ex-military investigator Jack Reacher, the brainchild of best-selling author Lee Child.

Video: Don't Mess with Tom Cruise as 'Jack Reacher'

In this brand-new video, Child details the origins of his vigilante hero and the action-packed thriller's journey to the big screen.

Directed by Christopher McQuarrie (screenwriter of Valkyrie, The Tourist), Jack Reacher also stars Rosamund Pike, Richard Jenkins, Werner Herzog, David Oyelowo and Robert Duvall.

Reacher hits theaters December 21.