When twelve spacecraft land at seemingly random locations all over Earth, US Army Colonel Weber (Forest Whitaker) recruits two experts to handle the 'first contact'. Military scientist Ian Donnelly (Jeremy Renner) is teamed with Dr. Louise Banks (Amy Adams) - a linguist whose mission is to determine the aliens' intentions. This is an urgent task. Although the craft appear to pose no immediate threat, their arrival sparks widespread public alarm and heightens international tensions between old foes. What Louise doesn't anticipate is that the work will illuminate a tragedy in her own past.