(NBC) — NBC’s sweeping, new 10-part nature documentary, “The Americas” premieres on Sunday night, narrated by Tom Hanks.

It didn’t take Hanks long to agree to be the documentary’s narrator.

“Have you ever seen ‘Planet Earth?’” Hanks said about being asked to do the series. “‘Yeah.’ ‘NBC is going to…’ ‘Yes!’”

And Hanks was not disappointed.

“There were times when I just said, ‘I cannot believe what I am looking at,’” Hanks revealed.

The series covers a region stretching through North and South America.

“It has all the superlatives you could ever imagine,” said Mike Gunton the executive producer of “The Americas.”  “OK, it doesn’t have elephants, but that’s about it. It has all the A-list animals, it has the biggest rivers, the oldest trees, the tallest trees. It’s an extraordinary place.”

But along with exotic locales, there are backyard ones too. Specifically, New York City’s backyard. It’s among the vignettes in Sunday’s first episode about the Atlantic Coast.

“Those raccoons are changing their behavior,” said Gunton. “They’re adapting to a new world.”

Sunday’s second episode covers Mexico and its waters, which produced the rarest of sights, four blue whales.

“They were chasing each other, they were racing through the water,” said Gunton. “They’re doing about 30 miles an hour. They’re the biggest animals that ever lived. Not only that, they’re leaping out of the water, crashing into the water. It was the most spectacular thing you could ever imagine. We didn’t expect that.”

Hanks told the “Today” show’s Savannah Guthrie he was continually astounded by the footage.

“I would just be waiting for somebody to ask, ‘What did you do today, Tom?’” said Hanks. “’What did I do today?’ And then I would talk for 45 minutes on what I just saw on ‘The Americas.’”

Sunday night is the viewers’ chance to be astounded.

“We live in an amazing world,” said Hanks.

The two-hour “The Americas” premiere begins on Sunday at 7 p.m. on NBC4, followed by the premieres of “Suits LA” and “Grosse Pointe Garden Society.”