After being available on PC and Linux for quite a while Hitman is now just about ready to make its transition to Mac as well. While Hitman was originally released in six episodes the Mac version will bundle all of them together into one package for the June 20th release date, so don't worry about the whole "episodic" thing as you're getting the full game.
As with the vast majority of AAA ports these days the Mac version of Hitman has not been handled by the developers themselves, but rather by Feral Interactive who have been quite busy these past few months. If the name doesn't ring a bell, you might know them from their work on the Mac and Linux versions of Total War: Warhammer, Dawn of War 3, XCOM 2, Tomb Raider, and so forth.
It is important to note, however, that the Mac version of Hitman will only launch with support for AMD graphics cards. Why exactly this is the case, I don't know, but Feral has said they will release more details regarding support for Nvidia and Intel graphics cards in the near future. If you would like to learn more I would recommend occasionally visiting the official website. And finally, here's a brief trailer showcasing the Mac version in action: