Firewatch comes to Mac, Windows, Linux, and PlayStation 4 on Tuesday. The Mac version is via Steam, where it's available for a preorder discount of US$17.99 (regularly $19.99) now. According to the developers, "Firewatch is a mystery set in the Wyoming wilderness, where your only emotional lifeline is the person on the other end of a handheld radio." It's set in 1989, meaning no smartphones or even cellphones. The trailer looks great. Check it out.