Director Bryan Singer continues to post behind-the-scenes photos from the set of X-Men: Days of Future Past as shooting moves at a brisk pace throughout Canada. Today, he offers a tease of Magneto's (Ian McKellen/Michael Fassbender) super fast mutant son Pietro Maximoff, better known to most as Scarlet Witch's brother Quicksilver. Check out the mailbox of this latest addition to the huge ensemble cast, played by Evan Peters.