WATCH: Sam Smith, Fifth Harmony Do 'Carpool Karaoke'

Sam Smith hopped into the passenger seat of James Corden's SUV for an episode of Carpool Karaoke that aired on Wednesday's The Late Late Show.

The two men performed bits of Smith's new hits "Too Good At Goodbyes" and "Pray" as well as his older songs "I'm Not The Only One," "Money On My Mind" and "Stay With Me."

Smith credited Corden with bringing attention to "Lay Me Down," a track from his 2014 album In The Lonely Hour.

"You did a tweet saying that you loved that song," Smith recalled. "I think I was working in a bar at the time. I was just like, 'Oh my God that's amazing that he liked my music.'"

Smith confessed to forging a letter from his father to get out of school so he could attend a Lady Gaga concert. "The excuse wasn't great," he recalled. "I said I was going to a funeral."

The singer also shared that he's perfected the art of the one-night stand.

Corden asked Smith to explain his love for Fifth Harmony. "When I hear them I feel free," he replied. "I feel alive. I feel like the woman in me is on fire.

"I'm just obsessed with them. I'm a Harmonizer."

So, it was quite a surprise when Corden pulled over so the members of Fifth Harmony could pack into the back seat.

Watch all the fun below: