Today, there are probably few who even remember it or have any expectations left, but in 2012 it was revealed that Splinter Cell would be made into a movie. The following year, it was confirmed that John Wick producer Basil Iwanyk would be in charge of production, and in 2014 it was announced that Tom Hardy would play Sam Fisher.
But since then, there's been a complete silence from the project, and now it's been announced that the reasons for this are exactly the same as you've probably already figured out. Speaking to The Direct, Hardy said it's dead:
"That movie would have been awesome... Just couldn't get it right, script-wise, budget-wise. But it was going to be great. We had a million different versions of it, but it was going to be hardcore and awesome. That's one of the ones that got away, which is really sad."
We won't be completely without Splinter Cell though, as Ubisoft is working on a remake of the first game. Furthermore... if it becomes a big success, we'd be very surprised if no movie company wants to have another attempt to film Sam Fisher's adventure.