“Double Take” is episode twelve of season five of Eureka.
In the previous episode, “Mirror, Mirror”, Carter had discovered the missing smart dust controller, the bio-printer – which was printing himself – and several other people, who were all unconscious. Plus, a conscious Holly and copies of the unconscious people. Holly is copying the entire town.
The NPCs from the Matrix are trying to get the Astraeus crew back into virtual Eureka. This time, they are planning to take the entire town and replace them with duplicates. With the exception of Holly and deputy Andy, who are in their original bodies, the others are downloaded NPCs.
The, ever decreasing number of real people, have to try and stop Holly whilst the entire town goes through Invasion of the Body Snatchers – and yes, one of the characters does call the replacements pod people.