EXCLUSIVE: How Christopher Nolan's 'The Odyssey' Pushed Cast to the Limit

Filming the big-screen blockbuster The Odyssey was no picnic – with the actors living like it really was 1200 BC.

RadarOnline.com has uncovered on-set secrets of director Christopher Nolan – who banned 21st-century must-haves, including cell phones, water bottles and even UGG boots while adapting Greek poet Homer's epic work.

According to insiders, Hollywood perks like fancy dressing rooms and first-class transportation were also no-nos for some of the film's cast.

What's more, conditions on set were so brutal that Matt Damon – who played Odysseus on his roller-coaster trip home from the Trojan War – admitted: "It was the hardest movie I've ever done."

Damon appeared to nearly drown in one scene and other scenes were filmed on a real Viking longship on the Mediterranean Sea – with seasick actors filmed vomiting over the side.

Another physically demanding scene was shot during Iceland's "white nights" period of 24/7 daylight.

In another gripping scene, the saga's Trojan Horse is stuck in an icy sea with actors, including Jon Bernthal, actually submerged inside it for hours.

Unlike many directors, Nolan doesn't use digital effects – and that meant his team had to build a towering 60-foot puppet version of the horrifying man-eating Cyclops.

Then, the production crew and actors shot a key scene with the Cyclops in darkness in a cave with only real firelight used to create a shadowy effect.

But Nolan's gambles on recreating Homer's retelling of classic Greek mythology paid off – with The Odyssey banking a boffo worldwide box office of $264million in its first weekend.

Oscar-winning actress Lupita Nyong'o – who plays the dual role of Helen of Troy and her twin sister Clytemnestra – said Nolan's banning of cell phones played a key role in the film's success.

Without phones, "Everyone is present, everyone is ready, alert and doing their bit to keep the train on the tracks," she said.