Batman: Arkham Knight was released with a number of issues for the PC. Shortly after, Green Man Gaming announced a refund program for after the patch, if your game still doesn’t work. Steam also has a refund program in place for those not satisfied with the game.
Warner Brothers Interactive has acknowledged the issue on their forums, and came out with a solution that may help you temporarily: lower your settings. Although the game won’t look as good, this may fix any issues that you are having with the game until the hotfix can be released.
The list of what you can do to help fix the game is extensive, and I highly suggest reading it and trying the fixes for yourself. This isn’t a permanent fix, and may not work for everyone. Warner Brothers is still attempting to work with Nvidia and AMD to fix the issues, however, Warner Brothers is stressing to make sure your video card drivers are up to date when attempting to play Batman: Arkham Knight.