CinemaCon: The Rock shows off 'Jumanji,' trash talks Leonardo DiCaprio

LAS VEGAS —  Leonardo DiCaprio suffered through snow, freezing waters and one memorable onscreen bear attack to earn his best actor Oscar forThe Revenant.

But that's nothing compared to what the stars of Jumanji (in theaters Dec. 22) went through making their film in Hawaii, according to Jack Black and Dwayne Johnson.

The Jumanji stars were on hand to unveil new footage Monday night from the fantasy adventure film during Sony Pictures' presentation at CinemaCon, the annual convention of theater owners.

"It sounds like, 'Oh, man, that must have been paradise. How fun was that?' The truth is it was pure hell," said Black, keeping a straight face. "Because if you go deep in the jungles of the Hawaiian islands, in the nooks and crannies, it's pretty hellish: the mosquitoes, the heat, the hellish terrain.

"A lot of people make a big deal about how awesome it was that Leonardo DiCaprio braved the ice-cold tundra in The Revenant. Well, I don't want to hear his whining. You try to make a movie in Hawaii! I don't want to hear it, DiCap."

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"And that's just one bear, I’m calling (bull) on that," added Johnson, referring to DiCaprio's famed CGI bear fight scene.

Johnson, who is an executive producer of the film based on 1995's original Jumanji, described meeting that film's star, Robin Williams, on the CinemaCon stage.

"I just said, 'I’m such your biggest fan.' I was completely fanboying," he said.

The new film is respectful of the original. "We wanted to make a movie that was not only phenomenal and paid homage, but something that had evolved," Johnson said.

The clip reveal featured four high-school students in detention who are sent to clean up an abandoned school basement, only to discover an old-school video game in the rubbish. Once the students begin to play, they're transported to the Jumanji world as their video-game characters. The jock loses girth and turns into the diminutive character played by Kevin Hart, the popular girl is transformed into the round, studious Professor Shelly Oberon (Black) and the allergy-prone nerdy kid becomes the massive Johnson.

Through their unlikely avatars, the students have to escape the fantastical Jumanji world with the help of a guide played by Nick Jonas, who was also in attendance at CinemaCon.

Johnson started the Jumanji session by promising the crowd: "You all want something big, something bold, so I'm going to get naked."

That promise did not materialize.

The Sony presentation also included the dreamlike first footage of the film adaptation of Stephen King's The Dark Tower. 

Dark Tower (out July 28) stars Idris Elba as the gunslinger Roland Deschain, who protects the world against a mysterious Man in Black (Matthew McConaughey).

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