Perplexed, Corden asked if they could perform the unreleased song.
"You don't wanna know," Kiedis insisted, "You say that now, and then you'll know and be like 'eww I should have listened'."
Flea went on to explain that they came up with the strange song when they were 15 after using marijuana in the woods. Flea and Kiedis then sang a snippet of Heme Leme, comprised mainly of gibberish lyrics.
"Are you sure it was just marijuana?" Corden joked after hearing the strange song.
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Later, Corden challenged Kiedis to a wrestling match.
Corden pulled the car over so the pair could have at it on the front lawn of a random person's house.
The "man wrestling" ending up consisting largely of Corden giggling before Kiedis wrestled him to the ground.
"I didn't see that coming, Kiedis," Corden said after his defeat to the Under The Bridge musician.
Watch the full 15-minute long ride below:
- nzherald.co.nz