“Miller’s Crossing” is episode nine of season four of Stargate: Atlantis.
Rodney McKay is convinced by Zelenka to get help from his sister, Jeannie, with a problem with the Replicator code that they have been stuck on for some time.
Shortly after McKay emails Jeannie, she is kidnapped, and then Rodney is too.
The kidnapper wants them to fix a problem with the nannites his company is working on, so that they can cure his dying daughter. To give them an incentive, he injects Jeannie with the same faulty nannites. They think they have fixed them, but there are some unanticipated side effects.
The episode revolves around the often amusing relationship between McKay and his sister, and he ends up asking for help from a less than popular source.