Beverley Barlowe uses the stolen DED device and the Bridge device (someone needs to come up with better names for these things) to send Dr. Grant back to 1947. Of course things don’t go according to plan and both Grant and Jack are sent back to the past while Allison appears to be fatally wounded in the present. Jack and Grant break time traveler protocol by purposely altering the past in an attempt to save Allison from her tragic fate.

Jack, Allison, Jo, Fargo, and Dr. Grant all begin to hallucinate. Each is followed and provoked by a specter from the past that they have unresolved issues with (Jack sees Nathan Stark!); Beverly Barlowe manipulates Dr. Grant, convincing him to sabotage a weapon being developed at GD.

Synopsis: Objects from the 1940s mysteriously materialize throughout town while Warehouse 13’s Claudia Donovan (Allison Scagliotti) visits.

Review: Claudia Donovan on Eureka! How cool was that? No, really. How cool was it? I don’t watch Warehouse 13, so I have no idea if her appearance was supposed to be exciting or if it was just a gimmick. But speaking as a completely objective person with absolutely no allegiance to Warehouse 13, this cross over episode was tastefully done—Claudia’s presence in Eureka felt natural (even if she was a bit gabby) and because her arrival wasn’t the central focus of the episode, I wasn’t distracted by how gimmicky the whole thing may or may not have been. The bizarre chemistry she had with Fargo was enough to make me want to check out Warehouse 13, if only to find out how a self-possessed quipster like her could be attracted to a wormy supergeek like the Fargonator. Eureka’s writing staff, however, lose creativity points for titling this episode “Crossing Over.” I’m sure they thought that they were being clever—a cross over episode about objects “crossing over” from the past to the present called “Crossing Over”—but they were wrong.

Unlike that excruciating “artifact” story arc from season 2, the high concept, time travel plot framing season 4 is fun, exciting, and already full of promise.

Here we are. Finally, the season finale for one of the best television shows on cable. Bill Adama is set to lead a team of volunteers on a suicide mission around the orbit of a black hole to rescue Hera, who has been kidnapped by Cylon Numero Uno.

Galactica is being dismantled, and the crew is preparing to move to the other ships in the fleet, including the Rebel Cylon Basestar. During this process, Adama plans a rescue mission for Hera while various members of the fleet flash back to their lives on Caprica before the fall.

The Cylons aboard Galactica confer with the Admiral on how to mount a rescue mission for Hera, while Boomer is well on her way to bringing the child to Number One. Meanwhile, Adama struggles with the decision to abandon the Battlestar.

With Boomer in the brig of Galactica, President Roslin has been asked to extradite her to the rebel Cylon Basestar to be tried for treason. Tyrol fears that she will be executed and arranges her escape, only to learn she has a secret plan.

Ellen, the final Cylon returns to Battlestar Galactica to be reunited with Saul, only to find that he has gotten Caprica Six pregnant

With the Galactica mutiny squelched, Adama is trying to pick up the pieces. Meanwhile, we learn the fate of the final Cylon.

The military coup led by Felix Gaeta and Tom Zarek spins into high gear. Meanwhile, Apollo and Starbuck are gathering support throughout Galactica with hopes of taking back the ship.

Felix Gaeta gets in bed with Tom Zarek, arranging a mutiny on Galactica and taking control of the Battlestar from the bridge. Plus, the two oldest dudes in the fleet show that they can still beat the holy crap out of a couple marines.

With the hopes of a home on Earth dashed, the fleet has fallen into emotional despair. Tom Zarek sees this as his opportunity to gain power over President Roslin, who has been in hiding since the discovery of Earth.

The loss of hope in the fleet, and particularly on Galactica, send the people into a massive depression. Admiral Adama struggles to bring sanity back to the fleet and offer a new hope.