Reacher, an ex-military policeman in a popular series of suspense thrillers, is described as 6'5" tall and weighing somewhere between 210-250 pounds. Clearly, those specs don't exactly match up with Cruise's leaner body type and 5'7" height.

Although he's confident he can do the role justice, Cruise admitted to being affected by the fans' critiques.

"Firstly, I'm very sensitive to it," Cruise told Empire magazine. He says series author Lee Child - who watched and approved of Cruise's reading - assured him that Reacher's imposing height "was just one element to his character" and not the beginning and end of the character.

"Reacher's size in the books is a metaphor for an unstoppable force, which Cruise portrays in his own way," Child explained, commenting on the fanboy brouhaha.

"This is Lee's book and Lee's character," Cruise acknowledged. "Him giving me his blessing is what made me do it. If he hadn't then I wouldn't have done it."

Tom Cruise with his tall(er) wife, Katie Holmes. Credit: Getty Images

So even if fans baulk at the idea now, Cruise can rest easy knowing the man who created Jack Reacher is certain that the right choice was made.

On his personal website, Child reasoned it out this way: "If we're going to have a movie, then let's have a movie star in it!" And truly, it's hard to nab a bigger action star than Cruise.

Furthermore, the film adaptation of "One Shot" will feature German director Werner Herzog — best known for helming and narrating documentaries like "Grizzly Man" and "Cave of Forgotten Dreams" — as the villain. And for the chance to witness a showdown between the critically - acclaimed German auteur and Tom Cruise, Jack Reacher can probably stand to lose a few inches.