This is what I'm reading...

Microsoft was aggressive in pursuing the idea of taking Halo to the big screen. It’s easy to understand why. The games, developed by Bungie Studios, were perfect blockbuster material: high-octane, intense sci-fi shoot ‘em ups with a dense mythology and storyline and a dedicated fan-base of millions. Combined sales of the first two Halo games grossed in excess of $600 million over four years, selling north of 13 million units. The movie biz looked on in envy.