Robert Rodriguez started out in the film industry much differently than other directors. The man behind From Dusk Till Dawn and Alita: Battle Angel wasn't always working with big budgets. In fact, his first feature film, El Mariachi, cost just $7,000, a number that other filmmakers told him was impossible. So how did he pull it off?

Well, for starters, he never intended for his film to hit the big time. Rodriguez had been interested in making movies since he was a kid. In college, he shot what Texas Monthly called "his first real movie", the student film Bedhead. It cost just $800 to make; his family and friends were the crew. After Bedhead became a minor success at film festivals, he figured he could make a feature film the same way. They would put together a short action movie for cheap and sell it to the Spanish video market. Everyone would make a small profit, and he would get the experience necessary to make his next film even better. It wasn't really important who ended up seeing the film. Rodriguez just loved making movies.

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He was forming an idea for a movie about a man who carries a guitar case full of weapons. He did the math and ended up figuring he would need about $8,000 (this number went down later). Some of this he could take from the various cash prizes Bedhead had won. But he still didn't know how he'd be able to raise the full amount before filming started in summer. Then he had an idea.

Wandering into town carrying a guitar case, El Mariachi passes a turtle.

All he needed to do was become a "lab rat" by volunteering for a paid clinical research study. Rodriguez had taken part in these sorts of trials before, so he pretty much knew how everything worked. In fact, money he had made as a guinea pig was what funded the production of Bedhead. But here he needed to make at least $3,000 to round out his budget. That would require spending at least a month confined to a research hospital, testing cholesterol-lowering medication. He figured he could use all the free time he would have to finish writing the screenplay for El Mariachi. He took on the attitude that the payment he'd receive was for writing the script, not for testing experimental drugs.

Rodriguez's book Rebel Without a Crew is full of anecdotes from his hospital stay. Different study groups had different colored T-shirts. The researchers called them by their T-shirt color, plus a number. Rodriguez became "Red 11." The Red group ended up getting extremely lucky; they could eat four meals a day from the cafeteria. The Teal Blue group, who were on a low-fat diet, ending up offering others bribes for bags of potato chips.

Everyone started getting stir-crazy, hoping the pill would make them sick so they could leave early with full pay. Thankfully, Rodriguez had a script to write. He started planning out scenes on index cards. When he had time to kill, he either spent it in the TV room or the board game room. He watched several films while he was there, among them the indie classic sex, lies, and videotape. He also found the perfect person to play the villain in El Mariachi: his bunkmate, Peter Marquardt.

Peter Marquardt as the drug lord Moco, standing with a henchman, in El Mariachi

Ultimately, Rodriguez's time as a test subject wasn't all that bad, outside of the boredom. There was only one blood draw a day, and the accommodations were nice. The Teal Blues ended up providing constant entertainment to everyone who didn't have to suffer with them. When the Reds got permission to go outside, some Teal Blues put on red shirts to sneak out with them. The Reds ratted them out immediately. Another time, a few of them broke into the cafeteria and stole a couple of snacks. The researchers caught them as soon as the results of the daily blood test came in.

And then, after a month of tests, Rodriguez's time as a red-shirt had officially come to an end. He celebrated his release by watching Terminator 2 in theaters with his wife.

The El Mariachi production was crazy, but Rodriguez knew how to do what he needed to with the available resources. His cost-cutting techniques helped the film come in more than a thousand dollars under budget. His film never made it to the Spanish video market: instead, it caught the attention of Hollywood distributors. Columbia Pictures starting testing it with audiences, and the support was unanimous. They sent it to Sundance, where it won the Audience Award (previously won by sex, lies, and videotape).

Rodriguez's success story wasn't the main selling point for the film, but it definitely drew a lot of attention. The theatrical release of the film was accompanied by a huge marketing effort by Columbia, and it paid off. According to Guinness World Records, El Mariachi is the lowest-budgeted film to make $1 million at the US box office. There are a lot of no-budget films out there, but none have matched the success of Rodriguez's fiery Hollywood debut.

In the years since, Rodriguez has directed a number of blockbusters, which he usually retains complete creative control over. His latest, the superhero film We Can Be Heroes, drew in 53 million Netflix viewers. He ended up making a movie (loosely) based on his experiences as a human lab rat: 2019's Red 11. And in true Rodriguez fashion, he did it on a $7,000 budget.

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