Season 5, Episode 12 – “Double Take”
The people of Eureka are being kidnapped and replaced by body-doubles one by one unless Allison, Fargo and Zane can figure out how to avoid capture and save their town.
Season 5, Episode 11 – “Mirror, Mirror”
A malfunctioning experiment cuts Eureka off from the world and threatens to destroy all human life in town unless Carter can figure out who sabotaged the experiment and stop them before it’s too late.
Season 5, Episode 9 – “Smarter Carter”
Dosed with a smart drug, Carter’s genius gets out of control as he starts to re-write the laws of physics, putting his friends and the whole town in danger.