Finneas Says Bond Theme Coming ‘Soon,’ Performs ‘Let’s Fall In Love For The Night’ on ‘Tonight Show’: Watch

In the break between the Grammys and this Sunday's (Feb. 9) Academy Awards, singer/songwriter Finneas swung by The Tonight Show on Monday night (Feb. 3) to perform the acoustic ballad "Let's Fall in Love for the Night" from his Blood Harmony EP and assure fans that the theme song that he and his sister, Billie Eilish, wrote for the upcoming 25th James Bond film is right around the corner.

After Fallon sang bits of some other famous Bond themes by Paul McCartney and Wings, Duran Duran, Carly Simon and Shirley Bassey, Finneas promised that they'd get a dart in the neck if he revealed anything. "I think I'm allowed to say soon, really soon," Finneas said about the as-yet-untitled track for No Time To Die, which is due out on April 10. "It comes out soon. And the movie's great… I can tell you something… it's great."

To be fair, Finneas couldn't say anything about what he and Billie will perform at the Oscars, though he did reveal how he decides which songs to keep for himself and which ones to share with his sister or another artist. "The only ones that I really keep are ones where I'm like, 'This is like a diary entry.' It's so personal that, like, I feel like only I can sing it," he said, noting that it's kind of annoying how much better his sister's voice is than his.

He also revealed some of the weird, everyday sounds that are buried inside such beloved songs as "Bury a Friend" and "Bad Guy." Always on the lookout for something to set his sound apart, Finneas said he walks around and records odd sounds to slip into songs, including the sound of a dentist's drill in "Bury" and the sound of the crosswalk chime in Australia that makes up what sounds like the hi-hats on "Bad Guy." 

Finneas returned later in the show for an acoustic, boppy performance of "Let's Fall in Love" backed by a bass player and drummer. 

Watch Finneas on The Tonight Show below.