Ray Jessel, at 84, would seem like an unlikely contestant to round out this season’s auditions for America’s Got Talent. And yet, NBC producers knew more than you.

In his pre-audition interview, Jessel told us that he only started performing at age 72.

After singing an original ditty he wrote and played on the piano stunned the audience and judges alike, Howard Stern told Jessel: “I’m really thinking you’re a breath of fresh air at 84 years old! When you first got up, I was kind of like, oh, he’s one of those acts that are a waste of time. I was going to buzz you, and then, all of a sudden, you kicked it with that brilliant lyric. And you know what? Good for you! You know? You’re a 84-year-old guy, you think 84-year-old guys have lost their sense of humor. You’ve got it in spades.”

What tickled their ivories so much? Take a listen to “What’s She’s Got” by Ray Jessel!

Heidi Klum asked if Jessel’s love gone wrong song really happened to him. Jessel claimed not quite, but yes “to a friend of mine.” Klum said his song was so catchy she worried her children would love it too much. “They’ll all be singing it tomorrow, and the next day, and the next.”

Jessel’s reply: “I like to write catchy tunes. They don’t write ’em like that anymore.”

He’d know.

Long before he began singing his own songs in cabarets in 2002, he’d been writing them for the biggest stars in music, TV and Broadway.

A Welshman by birth, Jessel earned a music degree from the University of Wales, then studied composition for a year in Paris before moving to Canada. He started as an arranger for a satirical revue there where he met and became songwriting partners with Marian Grudeff. They eventually caught the attention of producer Alex Cohen, who hired them to write a P.T. Barnum musical book first, before bringing them in to take over the score for the Broadway musical Baker Street in 1965.

Jessel’s next musical score with Grudeff was a revival of Hellzapoppin starring Soupy Sales in Montreal. That didn’t work. But their title song was recorded by both Jimmy Durante and Louis Armstrong.

In the 1970s, Jessel headed west to Hollywood and caught on as a sketch comedy writer, first for Dean Martin, and then for Carol Burnett, The Smothers Brothers, John Denver, Rich Little, Captain & Tennille and others. (See Ray Jessel’s IMDB page) “There were a lot of variety shows. I guess I did most of them,” Jessel recalled in a 2006 radio interview.

He only spent one season as a writer for The Carol Burnett Show, but has claimed writing “The Pail” sketch, which found Burnett visiting a psychiatrist played by Harvey Korman to figure the source of her deep-seated problems. “That’s one of the best sketches,” Jessel said in 2006.

Jessel said he also contributed jokes for a special that included an interchange between Groucho Marx and Bill Cosby, offering Groucho an answer to Cosby’s question on the economy with the quip: “Parts of my body have been unemployed for years.” Presumably, he’s talking about this special, but the only clip of it on YouTube is an edited version from a Spanish documentary that doesn’t include his joke.

Jessel also wrote for The Bob Newhart Show, and Head of the Class, but racked up many more credits for The Love Boat, including a special two-hour movie musical episode in its fifth season that starred Ethel Merman, Carol Channing, Ann Miller, Van Johnson, Cab Calloway and Della Reese with the regular Love Boat crew.

He also most memorably took shore leave from that TV gig in 1979 to help Richard Rodgers (late of Rodgers and Hammerstein) write lyrics for four songs in Broadway’s I Remember Mama, the final musical of Rodgers’s own storied career and lifetime.

More recently, Jessel co-wrote songs for Michael Feinstein and Shari Lewis. Feinstein even called Jessel “the millennium Noel Coward.”

You can hear Jessel talk about his career up to 2006 in this lengthy radio interview for “Dave’s Gone By” on UNC Radio.

And here is a longer version of the song you just saw him perform on AGT, “What She’s Got,” as a music video in 2012.

You can buy Ray Jessel’s 2009 album, “Naughty or Nice,” on iTunes: