Comic artist Brendan McCarthy contributed to the script of Charlize Theron and Tom Hardy’s on-set feud guaranteed that making the movie itself was no walk in the park.

However, the lengthiest delays in Fury Road’s production process occurred much earlier. The movie’s script took decades to finish, with various writers working on the project before moving on and numerous attempts at the Mad Max sequel being pitched, revised, thrown out, and reworked over the years. One of these, by eventual Fury Road co-writer Brendan McCarthy, even resembled a much later home invasion horror hit.

Related: Mad Max: Secret Meaning Of Fury Road’s Ending Quote Explained

McCarthy’s first pitch for Fury Road was, ittedly, set in the post-apocalyptic future, unlike director Fede Alvarez’s 2016 horror movie Don’t Breathe. However, the proposed story featured Max delivering a mysterious vial to a creepy benefactor in an isolated fortress home, and this was where the canceled Mad Max project started to resemble the twisty horror. Once there, Max realized the vial was full of human sperm and the villain was hoping to inseminate a captive woman—the exact plot point that shocked audiences when it was revealed to the big twist of 2016’s survival thriller/psychological horror.

Dylan Minnette and Stephen Lang in Don't Breathe

According to Kyle Buchanan’s book version of Mad Max: Fury Road that viewers got years later, the earliest antecedents of Immortan Joe using his captives as breeding stock can be found in this pitch. Similarly, Don’t Breathe featured a very different plot, but almost the exact same twist.

In Don’t Breathe’s version of events, an elderly blind man has his home broken into by a trio of miscreants looking to steal his significant fortune. However, the group instead find out he is harboring a captive woman in his basement who the villain intends to impregnate via a vial of sperm as twisted penance for her accidentally killing his daughter years earlier. Although the two movies have different plots in their finished theatrical cuts, both the Mad Max franchise installment and Don’t Breathe do make similar thematic points about patriarchal figures exerting a lethal amount of control over the bodies of others. In the Mad Max: Fury Road that fans eventually got, the comparison is much more subtle, but in the movie’s wild original pitch, the sequel’s story was surprisingly similar to 2016’s Don’t Breathe when it came to the pivotal central twist.

More: Why George Miller Almost Gave Up Directing The Original Mad Max