Typical story, uninteresting and predictable "twists" and basic shooter gameplay.
I don't see why people love it so much, there are MANY shooters that are way better than Halo. I tend to have quite a grimace on my face when my friend says come over we're gonna play some Halo, or how he wants me to try Reach next week. I only enjoyed ODST due to its co-op that's the only halo game i approve, everything else is just plain boring.