During season 4, Eureka experienced a blast from the past that sent the town through a worldwind of changes. Get caught up on the adventures here!
* Grace's malfunctioning PTSD recovery software causes the town to hallucinate.
* The group discovers that someone is targeting a weapon called a DED that releases an electromagnetic pulse powerful enough to destroy bridges and buildings.
* Grant, still unaware of Beverly Barlowe's evil intentions, helps her steal the DED.
* Carter and Allison are officially an item! Grant is totally out of the romantic picture.
* Jo and Zane discover that Beverly Barlowe's father, Adam, stole the plans for the Bridge
* Allison and Henry approach Beverly's hideout as Beverly tells Grant she stole the DED to power a new version of the Bridge Device. When they turn it on, their base explodes, injuring Henry and killing Allison.
* Carter rushes to the scene too late to save Allison. He finds and attacks Grant. The new Bridge Device is still running, and sends them back to 1947.
* Carter discovers the recording Grant made regarding him, and records an urgent message to his contemporary self to save Allison.
* Back in the present day, Carter receives the message in time and saves Allison's life, but Beverly Barlowe gets away.
* Zane won't be put off by Jo any longer. Since she won't answer his questions, he looks for information in a kiss. They are both bewildered, but Jo puts a stop to any further romance.
* Grant finally understands that he was wrapped up in an evil plot, and realizes he's a liability to Eureka. He gathers his belongings and bids a bittersweet adieu to his friends.
Wormholes start popping up all over, threatening to rip Eureka apart unless Carter can stop them.