Dedicated Foo Fighters fans kind of figured what was up when the band announced a special Cal Jam '18 pop up show at the Hollywood Palladium with Chevy Metal and the Holy Shits playing. Chevy Metal are the covers band featuring Foo Fighters drummer Taylor Hawkins, while Foo Fighters have played surprise shows in the past utilizing the Holy Shits name.

Sure enough, the free concert brought out a flurry of fans and those who turned out got a unique performance. Chevy Metal started off the festivities, with a covers-filled set mostly rooted in rock of the '70s era. Opening with Thin Lizzy's "Jailbreak," the band also worked out such favorites as The Knack's "My Sharona," the Rolling Stones' "Miss You," a double dip of Freddie Mercury with Queen's "Tie Your Mother Down" followed by the Queen/Bowie classic "Under Pressure." Queen's Roger Taylor also sat in with the band. They finished out with the Faces' "Stay With Me."

The addition of sometime special guest Dave Grohl to the Chevy Metal lineup for the set closing "Stay With Me" helped make for an easy transition as the Holy Shits (aka Foo Fighters) then took the stage for their performance. Whereas most Foo Fighters shows serve as a jukebox of the band's extensive catalog of hits, the Holy Shits used this unique opportunity to dig a little deeper.

While the show began with the staple "White Limo" and ended with the traditional "Everlong," the band broke out rarely played songs like "Watershed," "Gimme Stitches," "Weenie Beenie," "Low," "Hey Johnny Park," "Alone + Easy Target" and "New Way Home." Check out our photo gallery from the show and fan-shot video below.

The Cal Jam '18 pop-up performance was a precursor to this fall's second staging of the festival by the band. The 2018 edition will take place Oct. 6 in San Bernardino, Calif. at the Glen Helen Park & Festival Grounds with a lineup that includes Iggy Pop, Garbage, Tenacious D, Silversun Pickups, Greta Van Fleet, Manchester Orchestra, Slaves, Thunderpussy and more. Get ticketing details here.

Chevy Metal Perform "Under Pressure" With Special Guests Dave Grohl + Roger Taylor

The Holy Shits Perform "Gimme Stitches"

The Holy Shits Perform "Low"

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