The Doppelganger - S1.E7

After touching a mirror, Alex finds himself transported to 19th century Italy and is horrified to find that he is not the hero of the myth, but rather the doppelganger of the painter Giacomo. When he figures out that his mere presence is slowly killing the real Giacomo, Alex is determined to set things right and not let an innocent man die. But after helping Giacomo, Alex returns home and finds out that he has brought someone with him - a doppelganger of his own!