Following its accidental launch the Astraeus returns to Eureka and the crew discovers four years have elapsed in an instant. The crew quickly learns leadership has changed, procedures have changed and relationships have changed while they were gone and none of it for the good.
Warren Hughes makes one of unexpected visits to evaluate the Astraeus crew. Unfortunately his evaluations coincide with crew members' tendencies to swap minds with Jack. And some of the swaps happen during amorous activities that further stress the relationships of the crew's lovers.
Fargo is convinced that Holly is still inside of the Matrix computer, but the DOD is determined to wipe its hard drive clean -- losing Dr. Marten forever.
Eureka celebrates Feynman day with a plethora of practical jokes. While mostly harmless the jokes make it challenging to identify the real catastrophes Eureka is so prone too.
Allison's also brilliant brother visits the newlyweds to give Jack a hard time but Jack's intellect rises to the occasion. Henry and Zane work on freeing Holly from her virtual reality cage while struggling just to keep her alive.
Jack's idea of a romantic honeymoon doesn't quite mesh with Allison's. Holly tries on her new body. Jo and Andy followup on an investigation begun by Jack's predecessor.
Wormholes cause trouble on moving day. Or is moving day causing trouble with wormholes? While Jack tries to fix the wormholes Fargo is determined to something about moving day.