Eva Thorne arrives to aid in the aftermath, tasked with assessing the damage caused by Global Dynamics – a search now focused on a missing drone.

When a scientist vanishes without a trace from a hermetically sealed biosphere, Carter and Allison launch an inquiry. Separately, the Fixer endeavors to enhance the financial viability of Eureka’s operations.

The annual Eureka dog show is in full swing, a spectacle unlike any other. Elsewhere, Sheriff Carter finds himself amidst an unexpected tremor; Zoe wrestles with the decision to leave her demanding physics program; and Allison begins the ca…

The day of Allison and Stark’s wedding arrived, and for Carter, it felt like a repetition, a loop he was trapped within. Concurrently, his sister, Lexi, made a visit to the town.

The opening of an Egyptian queen's tomb at Global Dynamics precipitates a frantic search for her mummy.

The arrival of a superhero complicates Carter’s already challenging work. Simultaneously, Zoe and her companions face danger as Thorne initiates an underground search beneath Eureka.

The mayoral election in Eureka has been unexpectedly complicated by the appearance of a second sun, compelling Carter, Allison, and Zane to examine this phenomenon with increasing urgency.

A scientific discovery has unearthed a troubling truth, one with ominous implications. Zoe’s life hangs precariously in the balance, and Eva Thorne understands the source of her peril.

Following his dismissal as sheriff, Carter sought employment with the Department of Homeland Security. Meanwhile, Deputy Lupo made the decision to resign upon learning of the new sheriff: a remarkably affable automaton.

Following a malfunction during a DNA scan, Jo exhibits unusual behavior. The timing is unfortunate, as she is serving as interim sheriff while Carter is required to undergo a 48-hour Department of Defense recertification.

Dr. Tess Fontana reactivates Section 5, resulting in inanimate objects exhibiting movement, a phenomenon potentially linked to poltergeist activity.

Carter is drawn into a frantic pursuit of something growing to monstrous proportions when a series of increasingly elaborate pranks takes a lethal turn. Meanwhile, longtime adversaries from Area 51 arrive in Eureka for a bowling tournament.

The teenagers of Eureka, seemingly guided under the influence of a dream, converged on a field. There, they methodically assembled an odd construction from salvaged metal and discarded electronics.

The return of Henry’s vessel stirred a disquiet in Carter, a chilling suspicion that it might be connected to the unsettling electrical disturbances plaguing the town.

Allison’s baby shower yielded a bounty of gifts mindful of the environment, but the pleasant occasion took a sharp turn with the discovery of a drowned scientist, found in a place where such a fate seemed logically impossible.

The sonic cleaning employed by Global Dynamics occurs during a period when the people of Eureka experience a peculiar form of memory loss. Simultaneously, Allison’s labor begins.

Tess found her first day as interim head of Global Dynamics unexpectedly overwhelming when a sudden ice age descended upon Eureka, coinciding with the return of someone she knew well.

The season culminates with Tess facing a career decision: an opportunity awaits her in Australia. Meanwhile, Zoe stands ready to embark on her journey to Harvard. And Carter must grapple with an unusual energy anomaly detected above Eureka.