The 1964 passport of Motown legend Marvin Gaye "literally fell" into the hands of a Detroit man who purchased one of Gaye's albums at an estate sale for around 50 cents.

The man, who appeared on Monday's episode of the PBS series "Antiques Roadshow," told the show's appraiser, Laura Woolley, that he bought a few Gaye albums at an estate sale at the Detroit home of a late Motown musician.

"When I got home, I was going through them and out of an album fell this passport," the man told Woolley. "So it literally fell into my hands."

Robin Thicke Responds to Accusations of Ripping Off Marvin Gaye

The man, who was not identified but described himself as a longtime employee of Detroit's Motown Museum and a Motown collector, was in for a shock when Woolley told him how much the passport was worth.

"I wouldn't put less than $20,000 on the passport if you were to insure it," Woolley said.

Woolley noted that the passport was made after Gaye added the "E" to the end of his name after signing as a solo artist with Motown. She also said the passport's value was increased by the sentimental value attached to such a personal possession of the "I Heard It Through the Grapevine" and "Let's Get It On" singer.

"People love passports because they also show where he was all over the world, what he's doing during these years. He's obviously traveling, he's touring," Woolley said. "People also like them because we know that they're real signatures, because you have to sign your own passport."

The owner of the passport did not indicate what he planned to do with the memorabilia and was left nearly speechless after learning its value.

"Are you kidding me?" he asked Woolley. "Wow. I never would have thought. I mean, I'm just shocked. I mean … wow. Oh gosh, thank you."

Gaye was famous for his R&B hits like "How Sweet It Is (To be Loved By You) and "Sexual Healing." He died in 1984 at the age of 44 when he was shot in the chest by his father at age 44.