TORONTO (AFP) - Oscar nominees Benedict Cumberbatch and Michael Shannon electrified audiences at the Toronto film festival on Sunday with their portrayals of Thomas Edison and his rival - in the race for marketable electricity - George Westinghouse.

The Current War's director Alfonso Gomez-Rejon described Edison as someone "who came from a world of spontaneous invention without really seeing the purpose for it at first, and created a purpose for something".

In contrast, he said, "Westinghouse could immediately contextualise something and see how it could be greater for society".

"The rivalry between them was interesting," Gomez-Rejon said, because of "what it said about the world and how we can, through invention and technology, leave it better than how we found it."

Cumberbatch said he knew very little about Edison before taking on the role.

"I really was in the dark," he quipped.

His portrayal of the American icon is alternately sympathetic, and not.

Shannon faced a challenge in preparing for the role because Westinghouse destroyed all his personal papers before his death.

But before the start of filming, Gomez-Rejon found a rare book about Westinghouse and shared it with the actor.