According to Deadline, Adams would play an "expert linguist ... recruited by the military" to determine whether newly-arrived extraterrestrials are friendly (like Superman) or antagonistic (like Zod). It's based on a Nebula Award-winning novella by Ted Chiang, first published in 1998; Eric Heisserer wrote the screenplay; his credits include the scripts for the remakes of A Nightmare on Elm Street and The Thing, as well as writing and directing the recent Paul Walker vehicle Hours.
Villenueve made a big splash with last year's one-two of Enemies and Prisoners, and his involvement suggests a thriller that will take chances with its subject matter. Adams can certainly hit it out of the park with the right material, so this is a combination that is very intriguing.