The Original xXx 2 Was A Buddy Movie Between Vin Diesel & Ice Cube
The original, unmade version of xXx: State Of The Union was more of a buddy comedy between Vin Diesel's Xander Cage and Ice Cube's Darius Stone. The goal with 2002's xXx was for Sony to build itself a James Bond-style spy series for the 21st century. Instead of a suave, martini-sipping British spy, it focused on Vin Diesel's Cage, an extreme sports addict with a healthy disregard for authority. The movie was a success, but Diesel got cold feet about the direction xXx: State Of The Union was taking and left the movie.
The xXx series nearly took a more anthology approach from that point, with the plan being that each film would feature a new xXx agent in the lead. Ice Cube was thus cast as Darius Stone, a former Navy SEAL who is reluctantly recruited by Samuel L. Jackson's Gibbons to stop an attempted Washington coup. In contrast to the first film, xXx: State Of The Union was a box-office dud upon arrival and was lambasted for lazy writing, bad CGI and - the biggest crime of all - just not being much fun.
The paranoid conspiracy thriller angle helped set xXx: State Of The Union apart from the first xXx, but it quickly became clear a third entry wasn't happening. While xXx 2 was being developed, there were two screenplays being worked on; one saw Xander Cage fighting modern-day pirates, while the other found him mixed up in the coup of the final movie. In the documentary "From Convict to Hero: The Making of 'XXX: State of the Union," screenwriter Simon Kinberg revealed his original directive when penning the script was to make more of a thriller than an action film, and his version of xXx 2 saw Vin Diesel's Cage working with Cube's Darius Stone.
Of course, this original version of xXx: State Of The Union was heavily rewritten after Vin Diesel left. Director Lee Tamahori stated around 70% of the original screenplay was tossed out when Diesel left, with Stone originally being a friend and ally to the character. Stone was described by Tamahori as having a major supporting role and appeared to function in the story in a similiar way to Xhibit's Zeke. If the Vin Diesel - whose Cage was "killed" offscreen in the sequel - version of xXx: State Of The Union had reached screens, it's also unknown if Ice Cube would have been signed to play Darius Stone either.
That said, having Xander Cage and Darius Stone teaming up for xXx: State Of The Union, and having those two characters bounce off one another, sounds like it might have made for a more enjoyable sequel. Fans of the xXx series got a tease of that buddy movie energy between Vin Diesel and Ice Cube when they briefly shared the screen in 2017's xXx: The Return Of Xander Cage, but time will tell if they appear in the next entry together.