Pearl Jam must have felt a mighty presence in their territory -- Seattle -- last night, causing them to rise and recruit. Eddie Vedder and Mike McCready crashed Conan O'Brien's stage show last night (April 19), with the frontman playing three tunes and the latter guitarist joining him on the last, a cover of the Who's "Baba O'Riley."

Vedder played his mandolin-backed "Rise," from the 2007 film "Into the Wild" (yes, fans, Kristen Stewart was in that one) as well as his take on John Lennon's "Oh Yoko" -- naturally changing the lyrics to "oh Coco."

"There's something that happens when you play very small instruments," said Vedder, hoisting his ukelele for the latter. "It somehow creates the illusion that you're tall -- an illusion that's completely shattered as soon as Conan O'Brien stands next to you."

Check out a couple of the videos from the night below.

This comes a week after O'Brien did a little music stunt-work of his own, playing Radiohead's "Creep" and Gloria Gaynor's "I Will Survive" for fans. The former has some unbearable cockney accent and some excellent new lyrics (something about a chimbley sweep) and the latter... well, his beard grew very long.

Oh, do let this be a trend. All the way to the point where Thom Yorke plays special guest, to show who's really Team Coco.

Follow HitFix’s Katie Hasty on Twitter for more music and movie news at /katieaprincess.