Foo Fighters had been dropping teases all week, so it wasn't too much of a surprise, but the surviving members of Nirvana reunited at Cal Jam 18 on Saturday (Oct. 6) in San Bernardino, Calif. Dave Grohl had a little fun with the crowd after Foo Fighters finished the crux of their set, showing footage from backstage, with the camera initially on him, then showing Krist Novoselic and Pat Smear as well, with the crowd getting increasingly louder. He then turned the camera to his two other friends -- Joan Jett and Deer Tick's John McCauley, who handled vocals for this special occasion.

The encore was a six-song Nirvana set divided evenly between McCauley, who went first, and Jett. McCauley led the band through "Serve the Servants," "Scentless Apprentice" and "In Bloom," before letting Jett take over for the night's final three tracks -- "Breed," "Smells Like Teen Spirit" and "All Apologies" (with the latter finding Novoselic moving over to accordion).

Prior to "All Apologies," Novoselic and Grohl thanked the crowd, with Krist asking for a big cheer for the late Kurt Cobain and then seeing the place erupt.

Novoselic had performed earlier in the day with his band Giants in the Trees as Dave Grohl watched on from the side of the stage and eventually sat in on drums for a song. Deer Tick performed in the early evening hours ahead of the Nirvana performance. Meanwhile, Jett was the big surprise, as she was not originally on the bill. However, her Bad Reputation documentary screened for festival goers on Friday night.

Check out fan-shot footage from the performances below, see the pre-stage tease in the fan-shot video above, and stay tuned for our recap and photo gallery from Cal Jam '18.

Joan Jett With Nirvana, “Smells Like Teen Spirit”

Deer Tick’s John McCauley With Nirvana, “Serve the Servants”

Deer Tick’s John McCauley With Nirvana, “Scentless Apprentice”

Deer Tick's John McCauley With Nirvana, "In Bloom"

Joan Jett With Nirvana, "Breed"

Joan Jett With Nirvana, “All Apologies”

Deer Tick's John McCauley Performing With Nirvana

Kathy Flynn, WickedGoddessPhotography.com

Musicians Fans Most Want Back in Their Old Bands

10 Best Foo Fighters Songs