Last summer’s “The Old Guard” is full of big deals that shouldn’t be big deals anymore. The superhero action movie stars two women, one of whom is Black. Two other members of the superheroic Guard — both men — are in love with each other. A Black woman, Gina Prince-Bythewood, directed the Netflix hit, one of the streamer’s Top 10 most popular original films. That is all, by 2020, still groundbreaking. So let’s get to the story. Charlize Theron plays Andromache the Scythian, Andy for short, leader of a small band of warriors who have been helping people in trouble for a very long time. Centuries in fact, because Andy and her crew — Joe (Marwan Kenzari), Nicky (Luca Marinelli) and Booker (Matthias Schoenaerts) — are immortals. When the action opens, they’re being hunted for their powers.