Stargate Atlantis: Season 2, Episode 7

2 - 7: Instinct

On an unexplored planet, Sheppard, McKay, Teyla and Ronon hike into a village at dusk. The startled inhabitants insist that they spend the night. Apparently, after darkness falls, a mysterious killer stalks the area, sucking the life from its victims. Sheppard and his team instantly guess what they're dealing with: a Wraith.