Leonardo DiCaprio & Tom Hardy of 'The Revenant'

Scandal, lies and electronic long johns? How Tom Hardy "cheated" and stayed warm on the set of The Revenant, while Leonardo DiCaprio froze! Our Julie Chang got the exclusive revelation!

The Revenant is the story of betrayal...and it seems Leo DiCaprio felt just that when Tom Hardy exclusively revealed to our own Julie Chang that he used electronic thermals while filming brutal winter scenes in The Revenant. With Leo sitting right next to him, Tom told Julie, "You could push this little button on the thermal and the whole thing lit up like an electronic blanket in the inside.". Leo's facial reaction to this revelation is classic! It's a look of surprise and disgust all at once. Leo had no clue that Tom had this secret to stay warm in the 40 below zero degree filming conditions!

The cast of The Revenant told Julie that they had to be extra efficient during the 7 month shoot because they only had 3 hours of daylight to film. Some days it got so cold that the cameras stopped working!

The Revenant is based on true life events of Hugh Glass, a frontiersman from the early 1800's, who was left to die by his own men after a bear attack. Leo not only endured harsh weather for the role, but he also ate real buffalo liver to keep his performance authentic! He told Julie it's was like biting into a water balloon. Yeek.

The Revenant opens Christmas Day.

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