Robert Rodriguez's apocalyptic zombie film Planet Terror is widely considered to be the better half of Grindhouse, the joint throwback effort made with his friend and longtime collaborator, Quentin Tarantino. The film currently boasts a 74% Fresh rating on Rotten Tomatoes, which is 10 percent higher than its Death Proof counterpart.

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Planet Terror follows a motley crew of small-town Texans doing everything in their power to fend off a grisly zombie incursion after a military experiment goes awry. Rose McGowan, Marley Shelton, Josh Brolin, Freddy Rodriguez, and Jeff Fahey star in the film, which turned 13 years old in April. For more on the production, check out these behind the scenes facts about the making of the film.

Conception

Planet Terror

Under the original title Project Terror, Robert Rodriguez wrote the first 30 pages of the screenplay while filming The Faculty in 1998. At the time, the Mexican visionary told actors Elijah Wood and Josh Hartnett that zombie flicks were poised for a big comeback.

Rodriguez wanted to be at the forefront of the horror subgenre's return and hurried to write as much of a script as he could. When he got stuck at the 30-page mark, Rodriguez began to be distracted by other film projects and let the script languish for nearly a decade before rekindling the project in 2006-07.

Dakota Block's Casting

After working with her on Sin City two years prior, Rodriguez specifically tailored the role of Dr. Dakota Block in Planet Terror for actress Marley Shelton.

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Dakota Block is a doctor and mother of a young boy named Tony. When her sadistic husband, William Block (Josh Brolin), discovers her sexual affair with Tammy (Staci Ferguson), he impales her hands with anesthesia. Left with a broken wrist and lack of dexterity, Block suffers an unimaginable loss after giving a revolver to her son Tony to protect himself.

Dakota's Window Jump

One of the most memorable shots in the film comes when Dakota escapes by leaping from the window into a pile of trashcans below. The shot was achieved by filming it twice while using a passing car to distract the audience from noticing the edit.

In the first shot, a stunt double was filmed falling from the original height of the window ledge onto a crash-pad below. The second shot featured the same angle with Shelton falling into the trashcans from a scaffold placed at a lower level. The two shots are joined by the image of a passing vehicle to make it appear as one continuous image.

Josh Brolin's Audition

While filming Planet Terror, Josh Brolin desperately wanted to audition for the Coen Brothers' No Country For Old Men. When Joel and Ethan Coen refused to let him try out for a role, Brolin had Rodriguez and his pal Quentin Tarantino light and film his audition anyway.

Rodriguez and Tarantino used a digital camera worth roughly $1 million to film Brolin's audition, with Marley Shelton reading lines as Brolin's wife. When the Coens saw the audition, the first thing they asked is who did the lighting for the audition. Brolin was eventually cast as Llewlyn Moss in the Oscar-winning neo-Western.

John Carpenter's Score

To set the mood while filming, Rodriguez reportedly played the soundtracks for John Carpenter's Escape From New York and The Thing. When it came time to score Planet Terror, he hired Carpenter to compose arrangements for the film.

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While Carpenter wrote the songs "Back to the Pod" and "The Crazies Come Out" for the film, Rodriguez ultimately took over the role of composer and designed the score for the film himself. Even so, snippets of Escape From New York can be heard throughout the film.

Rodriguez's Doctor & Real Estate Agent

To achieve the utmost authenticity, Robert Rodriguez hired a pair of non-actors from his personal life that he knew would give convincing performances on screen.

For instance, Skip the strip-club owner in the film is played by Skip Lessig, Rodriguez's real-estate agent. Rodriguez told Skip to be himself and to let his natural terse and gruff demeanor shine through onscreen. Similarly, the character is of Dr. Felix (Felix Sabates) was not played by an actor, but rather Rodriguez's real-life physician.

Cherry's Machine Gun Leg

One of the most iconic images in Planet Terror is the powerful machine-gun leg Cherry Darling (McGowan) uses to mow down blood-parched zombies. The effect was achieved by encasing McGowan's leg in a medical cast so that it would remain stiff and immovable. Green and gray first-aid tape was then swaddled around her leg to shroud the cast.

For the shot of Cherry firing bullets from her machine-gun leg on the back of Wray's motorcycle, the scene was filmed first and retouched with CGI in postproduction.

Lieutenant Muldoon

Lt. Muldoon in Planet Terror.

One of the staples of grindhouse cinema in the 70s was to feature famous movie stars in the marketing campaign, despite their limited appearance in the film. As a nod to this sort of false advertising, Bruce Willis is given high-billing in the credits, but only appears in a few scenes in the film.

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More specifically, Willis is never seen sharing the screen with any of his costars, implicating that he filmed his part very quickly and independent of the rest of the production. Even so, Willis is prominently displayed on many of the movie's marketing materials.

Rebel Rodriguez

When it came time to film the devastating sequence in which baby Tony fatally shoots himself in the face while left alone in Dakota's car, Rodriguez felt the material was so disturbing that he did not want to inflict psychological harm on the young actor.

As a result, he used his own son Rebel Rodriguez for the scene instead. Rodriguez was sensitive to killing a child in such a grisly way that he did not want anyone else's child to participate in the scene.

Death Proof Connections

While Planet Terror literally connects with Death Proof as a horror double-feature, several nods to Tarantino's film are planted in the film. For instance, Death Proof star Zoe Bell appears as a zombie chomping on a paramedic in Planet Terror. In addition to Bell, Marley Shelton, Rose McGowan, the Babysitter Twins (Electra and Elise Avellan), and Michael Parks as Sheriff Earl McGraw all appear in Death Proof.

The Bone Shack restaurant in Planet Terror doubles as Jasper's Garage in Death Proof, while packs of Tarantino's fictional cigarette brand Red Apple appear in both films.

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