Stephen Colbert kept Lord of the Rings movie details from Spielberg

Stephen Colbert refused to divulge any details to Steven Spielberg about his The Lord of the Rings movie because he was "terrified" of breaking his NDA.

The former late-night talk show host is currently writing a screenplay based on J. R. R. Tolkien's famous novel with his son Peter McGee and long-running LOTR scribe Philippa Boyens.

During a recent lunch with Spielberg, the famed director tried to pry information about the movie from Colbert, but the TV personality was too afraid to divulge any details.

"Spielberg says to me, 'All right, tell me everything about The Lord of the Rings film. Tell me everything.' And you sign all kinds of NDAs before you're allowed anywhere near one of these sets, and he knows that. And you know, there are lawyers, and I'm new to all of this, so I was super nervous," said Colbert on Jimmy Kimmel Live! on Tuesday.

"So I just said, 'Okay, so here's what happens: Frodo teams up with a time-travelling dinosaur!' And he goes, 'You can tell me, I'm Steven Spielberg, I know Peter Jackson.' And I was terrified to, I was afraid I would get in trouble, so I didn't tell him anything. And then later I told our writing partner Philippa Boyens, she goes, 'You idiot! He might have had a good idea, he's Steven Spielberg!'"

Addressing the Jurassic Park filmmaker directly, Colbert quipped, "Listen, Steven, if you're watching, I'm ready to take your call!"

Colbert's movie, tentatively titled The Lord of the Rings: Shadow of the Past, was announced in March. The film will depict the early chapters in The Fellowship of the Ring, the first volume in Tolkien's The Lord of the Rings story.

As a LOTR "obsessive", the Emmy-winning star said he feels like "the luckiest guy in the world" working on the script in New Zealand.

The cast and director of the movie have yet to be announced.