Check out a set image from The Flash.
Slight spoiler: Apparently, Stephen Amell and Robbie Amell help Grant Gustin battle the Reverse Flash.
Amell's new Arrow costume seems to be more - League Of Shadows inspired?
We also see all four characters are unmasked in front of each other, including Tom Cavanagh as Reverse Flash.
This looks to be from The Flash season finale.
Here is a larger pic: