Slash and Fergie don't just do it on record. They do it on stage. The Black Eyed Peas singer joined the Guns N' Roses / Velvet Revolver guitarist on stage during his appearance at the Oxegen Festival in Nass, Ireland on July 10.

Slash tore through a hit parade during his set, performing a mixed bag of GN'R classics such 'Nighttrain,' 'Mr. Brownstone' and 'Sweet Child of Mine' along with solo and Snakepit tunes, and for good measure, Velvet Revolver's 'Sucker Train Blues' and 'Slither.'

But the fireworks really erupted when he was joined by the hotter-than-hot Fergalicious for "their" song 'Beautiful Dangerous' as well as a cover of Heart's 'Barracuda.'

Fergie Ferg sings on the studio version of 'Beautiful Dangerous' from Slash's self-titled solo album. (The video for the song had to be edited due to its steamy content, where Fergie played a crazed fan who stalks Slash, eventually tying him to a bed and teasing him with a knife while dressed in leather. All of that was her idea, too.)

Overall, though, it's the duo's hi-octane version of 'Barracuda' that makes us think they should work together again in the future. Normally, Fergie isn't usually celebrated for the strength or range of her voice, but this video will certainly erase the notion that she's just eye candy. The girl can hit the high notes and hold her own against one of rock's most revered guitarists.

It looks like it was pouring rain, but the crowd seemed into it. So did Fergie, running across the stage and interacting with Slash and the other musicians.

Clearly, Slash has unleashed Fergie's inner rock star.

Watch Slash and Fergie Perform 'Barracuda' at the Oxegen Fest

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