| Plot |
| 3x01 - Bad to the Drone: |
| Eureka is threatened by an intelligent drone with "issues" after an anti-missile test. Meanwhile, Eva Thorne, nicknamed "The Fixer", after dismantling and rebuilding several corporations, arrives in Eureka to evaluate Global Dynamics' expenditures. |
| 3x02 - What About Bob?: |
| A scientist somehow vanishes from a sealed biosphere, prompting Carter and Allison to investigate. Meanwhile, the "Fixer" attempts to make Eureka's efforts more profitable. |
| 3x03 - Best in Faux: |
| The town's annual dog show segues into a canine malfunction; Zoe worries about the impact of the accelerated physics program on her life; earthquakes affect Allison's wedding plans. |
| 3x04 - I Do Over: |
| It's Allison's and Nathan's big day - but time got stuck in a loop. Only Carter seems to be aware that he lives the same day over and over again. Carter's sister Lexi arrives early and with baggage while we get a glimpse of Eva Thorne's plans. |
| 3x05 - Show Me the Mummy: |
| A search for a mummy ensues after a famed archaeologist opens the tomb of an Egyptian queen at Global Dynamics. |
| 3x06 - Phased and Confused: |
| The emergence of a superhero makes Carter's job more difficult; Thorne's subterranean search for a secret beneath Eureka imperils Zoe and her friends. |
| 3x07 - Here Come the Suns: |
| The race is on to find a new mayor. Thorne (Frances Fisher) endorses Dr. Herrera (Dean Marshall); Fargo (Neil Grayston) is backing Vincent (Chris Gauthier); and Zoe (Jordan Hinson) is campaigning for Lucas (Vanya Asher). Unfortunately, Zoe's political activism leads her to abandon her science project partner, Kylie (Margot Berner), with unexpected results. While the candidates play politics, Thorne shows Allison (Salli Richardson-Whitfield) a new chemical Zane (Niall Matter) developed. It will [...] (More) |
| 3x08 - From Fear to Eternity: |
| When a potentially world-altering scientific discovery from Eureka's past finally comes to light, can anyone be trusted with it? The question is far from rhetorical for Carter: Zoe's life is in immediate danger and Eva Thorne knows why.
Trust is becoming a rare commodity in Eureka. Jo is unsure of her relationship with Zane while Carter and Allison wonder why Eva Thorne (Frances Fisher) is so secretive about the underground bunker. The bodies that were found there are to be shipped out, by [...] (More) |
| 3x09 - Welcome Back Carter: |
| Following his termination as sheriff, Carter interviews for a job with the Department of Homeland Security. Deputy Lupo resigns when she learns the new sheriff is a very personable robot. |
| 3x10 - Your Face or Mine: |
| Carter takes a grueling recertification exam that tests him physically and psychologically; Allison pitches a town-wide DNA-monitoring security system to Henry that injures Deputy Lupo during the inaugural scan. |
| 3x11 - Insane in the P-Brane: |
| Objects become ambulatory after Dr. Tess Fontana (Jamie Ray Newman) reopens Section 5, which may be the work of poltergeists. |
| 3x12 - It's Not Easy Being Green: |
| Long-term rivals from Area 51 visit Eureka for a bowling tournament; Carter probes an escalating series of pranks. |
| 3x13 - If You Build It...: |
| A strange structure comprised of electronics and scrap metal is assembled in a field by Eureka's teenagers, who appear to have been manipulated while they were sleeping. |
| 3x14 - Ship Happens: |
| Henry's ship returns, and Carter thinks it may be linked to the town's deadly electrical anomalies. |
| 3x15 - Shower the People: |
| Allison's baby shower yields eco-friendly gifts and the discovery of drowned scientists in an area where drowning is impossible. |
| 3x16 - You Don't Know Jack: |
| A sonic cleaning at Global Dynamics coincides with a phenomenon that causes Eureka's citizens to develop a communal form of Alzheimer's. Meanwhile, Allison goes into labor in the third-season finale. |
| 3x17 - Have an Ice Day: |
| While Allison is on maternity leave Tess steps in and runs Global Dynamics. Zoe takes an aptitude test which shows what career she should pursue and the results doesn't match her expectations. Meanwhile, an ice-core taken from Antarctica is delivered to Eureka and things in Eureka gets very chilly. An old friend shows up to help out. |
| 3x18 - What Goes Around, Comes Around: |
| In the third-season finale, Tess receives a job offer in Australia, Zoe is set to leave for Harvard, and Carter must contend with a magnetic disturbance that's floating above Eureka. |