After John Sheppard is drawn to and touches a crystalline substance on a planet he and his team are exploring, several members of the expedition begin to have nightmares. Teyla dreams that Sheppard turns into a Wraith and feeds on her; and Dr. Jennifer Keller dreams she is called to sick bay to treat Teyla who is in excruciating pain while Sheppard looks on, apparently enjoying her suffering. Sheppard himself is fine but when the nightmares begin to spread to other members of the crew and one dies as a result of what happens in her dream, finding a solution takes on an even greater sense of urgency.
—garykmcd