Stargate Atlantis

Episode 4.17 - Harmony: McKay and Sheppard chaperone a young girl through a dangerous forest, at the request of her two older sisters. They face an old enemy. Source: SpoilerFix.com

Episode 4.19 - Outcast: Sheppard attends to some personal business, when he's approached by a woman who says she knows him. It turns out that she works for a lab where a replicator was built and it's on the loose on earth. Source: SpoilerFix.com