Ecks vs. Sever was meant to be an adaptation of the film Ballistic: Ecks vs. Sever starring Antonio Banderas and Lucy Liu. Publisher BAM! Entertainment optioned the game rights to the barely in production film and sent developer Crawfish Interactive to work, basing the game on a very early version the film's script. Though the film was delayed and radically altered from the original script, BAM! and Crawfish nevertheless proceeded with the original design and released the game--with no mention of the movie upon which it was based--on November 27, 2001, ten months before the film would debut. A version for PlayStation 2 and Xbox was also in production at Zombie Studios, but it was cancelled.
Ecks vs. Sever would be followed by Ballistic: Ecks vs. Sever, another FPS for GBA that was released in tandem with, and more closely followed the plot of, the final film and was positioned as a sequel to this game. Both Ecks vs. Sever games are widely considered to be superior to the film upon which they were based, which was ranked the "Worst-Reviewed Film of All Time" in 2007 by film review aggregator Rotten Tomatoes.