Director Oklahoma Ward and actress Nicole Alonso said they planned on making two sequels and even got offers from studios who wanted to produce them, but they turned them down because they all wanted to turn Alonso's character Tank into a typical horror movie sex object, which is something the distributors of the first film also wanted to do. The studios wanted to include scenes showing her taking a shower, having sex, running around topless or just be fully nude in most of the films. They even wanted scenes where various monsters would try to rape her. Ward and Alonso ultimately decided to try and finance the sequels themselves just like they did this one, but as of April 2021, they still hadn't made them or any other films since this one was released.
Nicole Alonso explained in an interview how she ended up starring in and producing this film: "Well, I actually met the director, Oklahoma Ward, when I auditioned for his first film and I got a small role in that. And then after that we actually became roommates for a while and so we were working together. And then after about a year we ended up dating, and then he and I kind of launched into this project together, Crawl or Die. He began writing it, and then we lived in L.A. at the time and we ended up moving out to Tulsa, Oklahoma to build the set and film the movie, and we just kind of worked on the whole thing together. So that's kind of how I have all these roles in it and got involved in doing all of that other stuff for the movie too."
Billed as the most claustrophobic movie ever made.
The director gave actress Nicole Alfonso several movies to watch and study the characters in the films to get a good idea of how he saw her character Tank. Most notably and most helpful were Alien (Ripley), Terminator 2 (Sarah Conner), G.I. Jane (Jordan O'Neill) and Domino (Domino Harvey). Alfonso said she found all those women, while tough as nails, to still be human and still be women. They had emotion and fears and struggles, but what made them badass and tough was they kept going even when things seemed hopeless. She also read the online blogs of a few female marines to get some insight on what it's like to be a woman in a male dominated field.
Writer/director Oklahoma Ward said he and star/producer Nicole Alfonso, who were living together, saved up enough money to make the movie over a three year period by giving up a car, living in a garage, not going out to dinner or taking vacations etc. During that time they also managed to buy a cheap broken down home, remodel it and sell it for a small profit. At that point they started building the tunnel set by hand, which took about a year.