Can somebody give me the likely plot for the avengers film next year?

i am assuming loki a villain and bruce banner is listed but not the hulk for the film there are 7 heroes in the film the most powerful and intelligent of which is thor then iron man black widow war machine hawk eye captain america like i think there has to be a team of villains and i am hoping for the abomination to make an appearence any idea what the overall plot may be