the film opens with a female member of a rock band crawls down a hallway in a palatial home
She begs for her life as a man pursues her
The rocker looks to her side to find another bandmate dead with his face split open
The pursuer catches up, and bashes the rocker’s head in with a hammer
Jumping ahead in time the Foo Fighters
a famous rock band
are meeting with their manager Shill to discuss their 10th album
Frontman Dave Grohl is suffering from a musical block unable to think of any new songs
Shill is not empathetic saying that he has debts to pay
and therefore, the Foo Fighters need to make a new record ASAP
Grohl says that he wants to try something different than recording
in a studio in order to get him past his block
Shill contacts a property manager named Barb Weems
to rent a house for them that will help the band find inspiration
The band including Dave Grohl, guitarists Shiff and Pat Smear,
bassist Nate Mendel, keyboardist Rami Jaffee and drummer Taylor Hawkins
arrive at the mansion from the beginning of the film
Weems shows them around the property
and Grohl has psychic visions of the slaughter depicted at the beginning of the film
Liking the atmosphere and being influenced by the supernatural
Grohl convinces the band to stay and record at the house
While setting up equipment
one of the crew members dies in an electrical accident caused by a spectral being
But Grohl convinces the band to continue recording at the house in his honor
However, Grohl remains uninspired
even trying to rip off a song made by another artist “cameo by Lionel Richie”
They also, meet next-door neighbor Samantha who tries to befriend the band
One night, after Grohl has demon-plagued nightmares
he awakens and follows a figure moving through the woods
He is led to a decrepit basement structure
Inside, Grohl finds a dead raccoon split open and nailed to the wall above a drain
He also finds an audio recording from a band, called Dream Widow
shown being killed at the beginning
He plays the recording and rocks out
However, the recording suddenly plays backward on its own and Grohl is possessed by an unseen spirit
The next morning, Grohl summons the band and plays an amazing guitar solo
He claims to have invented a new musical key the key of L
and gets the band to have a productive rehearsal
Grohl dismisses the crew “cameo by John
Carpenter” so that the band can continue recording on their own
That night, Grohl blows off a delivery guy
who has his own band and idolizes the Foo Fighters
The Foo Fighters continue to record
and the band members try to cater to Grohl’s increasingly fickle demands
When Samantha drops off cocaine-infused lemon bars,
she warns the band that murders occurred in the house
Grohl orders some groceries and the delivery guy is killed
when he follows demonic figures into the woods while making the delivery
That night
Grohl eats his steak raw much to the band’s disgust
As time passes, the song they are recording goes over 30 minutes
Weems visits and finds the house in a filthy condition
and the band reaching their breaking point with Grohl
Eventually, Shiff angrily confronts Grohl before leaving rehearsal to grill some lunch
While grilling, Grohl sneaks up behind him and kills him by burning him to death on the grill
Meanwhile, Hawkins finds the delivery guy’s disemboweled and beheaded corpse
The band wants to call the police
but Grohl confiscates their phones and car keys
demands they finish the song now in honor of the delivery guy
The band decides to meet secretly
to discuss Shiff’s disappearance and what to do about Grohl and the song,
which is now over 40 minutes
They ask Samantha about the house’s history
She reveals that she was a groupie for the Dream Widow band
She explains that the band and Samantha herself began
dabbling in the dark arts in order to enhance their music
and that the mansion is located atop a portal between Earth and Hell
The Dream Widow front man found a cursed book that was activated by sacrificial blood
the front man used raccoon blood to commune with demons
The demons eventually possessed the front man in an effort to record a hellish rock song
The front man killed his band while possessed,
but then killed himself to prevent the song from being finished
She says that the same demon is now possessing Dave Grohl and the band agrees
Smear and Mendel go to find the book as it contains an exorcism spell
Hawkins is sent to distract the now demonic-looking Grohl
Grohl kills Rami and Samantha and then finishes recording the song with Hawkins,
before killing him too
He also eats Shiff’s body as demons crave human flesh
Smear and Mendel find the cursed book hidden under the drain beneath the dead raccoon carcass
They are accosted by demons but manage to escape
Grohl pursues his remaining bandmates but they
manage to complete the exorcism spell to break the possession
Grohl pukes out the spirit of the Dream Widow front man
he then beats up the demonic front man
before the spirits of the Dream Widow band drag their front man to Hell where he can be tortured
As Smear, Mendel and Grohl walk to their van to leave the house,
they are confronted by Shill and Weems
It turns out that the pair are satan worshippers, that set everything up
Smear and Mendel try to hotwire the car so they can escape while Grohl fights Shill
Unfortunately, Weems confronts the bandmates and all three die
Grohl almost manages to kill Shill
but stops when Shill begins laughing at the realization, that the band completed the song
Shill notes that this song will save Rock and Roll and that it’s time for Dave Grohl to be a solo act
The film jumps ahead one year to a Dave Grohl solo concert An excited crowd chants his name
As Grohl prepares to go on stage to perform the demonic song his eyes turn black showing
that he is now permanently possessed
by evil