Of all the trailers and gameplay footage unveiled at this week's E3 event, one of the most impressive titles we've seen so far has to be Ubisoft's Rainbow Six Siege. This latest installment maintain's the game's team-based, tactical and close-quarters action, this time presented in a multiplayer format focused on short missions and mostly indoor environments. In the following gameplay demo, the scenario is a rescue mission in which a hostage is extracted from a two-story house. High tension comes from the tight spaces and a ticking clock, while the displays of teamwork include breach planning, shielding, and cover fire. Check out the video below, and look for Rainbow Six Siege to launch sometime in 2015.