Robert Plant, Jimmy Fallon Sing 'Duke of Earl' On 'The Tonight Show' [WATCH]

As usual, Jimmy Fallon is having all the fun.

He had rock legend Robert Plante (Led Zeppelin) on The Tonight Show Friday night, and decided to sing a doo-wop duet with some help from Loopy, an iPad app.

After some initial awkwardness, the pair pulled off a solid cover of Gene Chandler's tune "Duke of Earl."

Check it:

Plante released his latest solo album, Lullaby and... The Ceaseless Roar on Sept. 8.

Recorded with the Sensational Space Shifters in London, the record has reached as high as No. 10 on the U.S. Billboard chart, and hit the Top 5 in several other countries (including No. 2 in the U.K.).

"It's pretty virile stuff, and it has come from our countless hours of trudging the endless highways," he told Rolling Stone. "If we'd just met in a room somewhere, we'd have never gone anywhere near this."

He's also got a bunch of tour dates coming up. Check those out here:

09/27: Brooklyn, NY @ Brooklyn Academy of Music

09/28: Brooklyn, NY @ Brooklyn Academy of Music

09/30: Toronto, ON, Canada @ Massey Hall

10/02: Chicago, IL @ Riviera Theatre

10/04: Denver, CO @ Fillmore Auditorium

10/07: Los Angeles, CA @ Hollywood Palladium

11/09: Newport, UK @ Newport Centre

11/10: Bournemouth, UK @ O2 Academy

11/12: London, UK @ Roundhouse

11/14: Hull, UK @ City Hall

11/15: Glasgow, UK @ O2 Academy