A Nirvana reunion show with surviving members and a few special guests might be happening this weekend.

Foo Fighters' cryptic social media posts are leading us to believe the band will play a surprise gig at Cal Jam 2018.

Read more: Dave Grohl calls Foo Fighters’ latest music video a “Nirvana antithesis”

It all started with Foo Fighters retweeting an announcement from Cal Jam about the screening of Joan Jett's new documentary.

A few hours later, the band shared a video with a simple caption: "This is a Jam." The 10-second clip with really distorted audio is from said Rock and Roll Hall of Fame gig.

It shows Dave Grohl, Krist Novoselic and Pat Smear, as well as John McCauley  of Deer Tick.

Another interesting fact about the video is the audio is Nirvana's "Serve the Servants" played backwards, as Loudwire notes.

Foo Fighters and Novoselic's band Giants in the Trees are scheduled to play at Cal Jam in San Bernardino, CA on Saturday, Sept. 6. Plus, Joan Jett and Deer Tick are also on the festival's lineup.

Could this mean they are planning a special Nirvana reunion performance?

If it happens, the gig will follow a recent Nirvana reunion show that took place in Seattle in September.

Grohl, Novoselic and Smear got onstage together during a Foo Fighters show to perform “Molly’s Lips.” They did Nirvana’s take on the Vaselines’ tune during a hometown gig on Sept. 1.

On Twitter, Novoselic marked the occasion by referencing a seeming Nirvana in-joke about “Dan Grohl and Paul Smear.”

Foo Fighters are currently on tour in North America. Check out all the dates and cities below.

Foo Fighters tour dates

10/06 – San Bernardino, CA @ Cal Jam ‘18
10/08 – Phoenix, AZ @ Talking Stick Resort Arena
10/10 – Denver, CO @ Pepsi Center
10/12 – Kansas City, MO @ Sprint Center
10/13 – St. Louis, MO @ Enterprise Center
10/15 – Detroit, MI @ Little Caesars Arena
10/17 – Milwaukee, WI @ Fiserv Forum
10/18 – St. Paul, MN @ Xcel Energy Center

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