Tremors 7 has just made a dynamite addition to its cast. First off, yes, for those who perhaps haven't heard, a seventh installment in the long-running franchise is about to get underway. Franchise star Michael Gross is coming back once again as the gun-loving Burt Gummer in what is officially titled Tremors: Island Fury. This time around, he's going to be joined by none other than Napoleon Dynamite himself, Jon Heder.

Michael Gross is in every Tremors movie, as well as the TV series. As of late, he's been sharing updates regarding the next installment and recently made the surprising casting announcement on Instagram by sharing photos of the cast with Jon Heder amongst them. The post was shared with the following caption.

RELATED: Michael Gross Takes Us to Shrieker Island in Tremors 7 [Exclusive]
"The cast of #tremors seven!!!"

Also included in the cast will be Richard Brake, Caroline Langrishe, Jackie Cruz, Cassie Clare, Sahajak Boonthanakit, Matthew Douglas, Randy Kalsi, Bear Williams, David Assavanon, Boonma Lamphon, Aukrawut Rojaunawat, Owen Macrae, Iris Park and Mikey Black. One important item of note is that Jamie Kennedy, who has starred as Burt's son in the past couple of installments, Bloodlines and A Cold Day In Hell, will not be returning. But the real headline here is Jon Heder, as the actor hasn't been doing as much high-profile work in front of the screen in recent years, largely sticking to voice work. And this certainly makes for an interesting choice.

Jon Heder exploded onto the scene in as the title character in Napoleon Dynamite. The indie comedy, which was produced for $400,000, went on to make $46 million at the box office, cementing it as a huge hit. Heder then starred in a series of broad comedies such as The Benchwarmers, Blade's of Glory and Mama's Boy. This will be Heder's first real foray into the world of horror, unless you count The Sasquatch Gang, Ghost Team or his voice work in Monster House, and it will undoubtedly be interesting to see how he's utilized. We should note that he did play a zombie hero in the TV series Woke Up Dead and appeared as himself in the TV show Dead Grandma.

No character details were provided for any of the new additions at this time. As far as plot details go, Tremors 7 will center on Graboids that are illegally brought in to a new island resort by a rich playboy looking for a trophy hunt. Considering this is the seventh movie in the series, it's pretty amazing they haven't thought to do a "most dangerous game" take yet. But better late than never for old Burt Gummer.

Tremors was released in 1990 and starred Kevin Bacon in the lead role. A small desert town of Perfection is terrorized by giant, deadly worms that hide under the sand. The movie was a modest hit, but well-liked and spawned a series of sequels over the years. SyFy recently tried to make a new show that would have brought Bacon back into the fold, but only a pilot was shot and it never went to air. Tremors: Island Fury shoots in Thailand soon, but does not yet have a release date set. We'll be sure to keep you posted as further details are made available. Be sure to check out the post from Michael Gross' Instagram.

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The cast of #tremors seven!!!

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