No spoilers here.
Scripted by Billy Ray of Hunger Games and Captain Phillips fame.
It was odd reading a 24 story for the big screen. I think all fans of the show remember the multi-window ticking clock and tension every commercial break.
It is a 24 story:  Jack, Chole, governments, the brink of war. Which was written before the reboot(s).
It's shorter than I thought: 118 pages and an easy read. Billy Ray captured the essence Bauer. I don't think any fan of the show would be pissed about  the direction the franchise would have headed in. Not bogged down with backstory, just enough to let newcomers know about Jack's past. There are two characters you think are major players who wind up fading away.
I'd say the ending needed work. Jack was a bystander, not the judge, jury and executioner. Tony Gilroy or David Keopp probably would have been called into rewrite.