Tess has a job offer from Australia, Zoe is prepared to leave for Harvard and Carter has a magnetic disturbance above Eureka to contend with, in the third season finale.

It's Founder's Day in Eureka and everyone is in the spirit of the celebration until Jack, Allison, Henry, Jo and Fargo are transported back to 1947 where they meet some familiar faces along the way. Will they be able to get back to 2010 or will they be stuck forever in 1947 where Eureka is not a town, but an Army base.

Carter can't get into the Christmas spirit especially with the town surrounded by a force-field. Fargo organizes the GD holiday party, and Allison is full of holiday cheer.

Carter's duties expand to babysitting when Allison attends a medical conference, and Fargo finds his groove when a certain song is played. Meanwhile, a rocket scientist appears at Café Diem.

In the season finale - It's chaos in Eureka when an energy beam rips through main street but the Astraeus launch must go on...with or without Eureka intact.

The quaint town of geniuses is transformed into animated versions of themselves. Sheriff Carter and Allison Blake are secretly planning the perfect holiday surprise for their kids. But a mysterious kaleidoscopic wave of color crashes over Eureka, leaving the entire town and its inhabitants animated.

The Astraeus crew returns to Eureka four years later and must adapt to a myriad of changes, including a more oppressive version of Deputy Andy.

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.

Wormholes randomly materialize around Eureka as the Department of Defense is set to shut the town.