Inspiration can strike when you least expect it.

Charlie Puth revealed the surprising origin of his hit song "Attention" while appearing as a guest on the March 26 episode of Twin Peaks actor Kyle MacLachlan's What Are We Even Doing? podcast.

Puth shared how he often gets ideas while "running hot" from shows and high adrenaline, and that proved to be the case when was on his way to fly to a show in Japan in 2016 and he heard a "plucky" sound that got his creative juices flowing.

The musician, who brought a mini keyboard to the podcast, plucked out the tune that turned into the opening notes of the 2017 track. He explained that the notes were running through his head as he made his way through fans to get to his plane, and the lyrics soon followed.

"It was the first time I had fans show up at the airport, this was like 2016, so I was kind of excited, I feel like my hard work was finally paying off," he said. "So I just started repeating myself, 'We're running 'round, running 'round, running 'round, running 'round to the gate,' and then that turned into 'running 'round, running 'round, running 'round throwing that dirt all on my name,' which is of course the verse to my song 'Attention.'"

He continued, "I'm never good at explaining where songs come from. It's just kind of maybe God throwing something at me, and I just picked something in the air. I don't know, but that just fell into my brain."

The "Changes" singer, who recently welcomed his first child with wife Brooke Sansone, is preparing to hit the road for a new tour in support of his fourth studio album Whatever's Clever!, which drops Friday, March 27.

On What Are We Even Doing?, MacLachlan sits down with Millennial and Gen Z actors, artists, content creators and more to "talk shop, compare notes on life, and generally be weird together." Follow along with new episodes at iHeart.com.

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