What you need to know about Thanos before you watch Avengers: Infinity War

The upcoming “Avengers: Infinity War” has a lot going on in terms of cast. If you're not brushed up on all the previous Marvel movies, you'll probably be as lost as we are during the screening. Thanos is one of those baddies who's appeared in the movies here and there, but never had his own spotlight. Finally he'll "debut" as the main villain in “Infinity War,” so here's a refresher on what his deal is.