For a guy who's been taken somewhere forcibly, Hendrix is having a great time at GD. He says Zane has the right "dissolving chain" but in order for it to work, they'll need a made-up element called Francium 227AC that there's only less than an ounce of on the planet. Which is silly, but I'll go with it. Zane says there's a secret stash of the stuff at GD. Way to bogart all the Francium 227AC, GD. Zane and Jo hobble away to get some. Because they have left the scene, another character must step in. That character is Allison, who asks Hendrix if he knows why they're getting reports of earthquakes near the bunker. Hey, remember when Carter felt an earthquake and everyone just totally dismissed him because it was impossible for Eureka to have earthquakes? Apparently now, earthquake reports are instantly believed and investigated. Hendrix says it's because Eva made him rush his job. Allison, Jo, and Zane all realize that Eva sealed the bunker -- with Carter inside.
Fortunately, Carter and Eva have access to the room where Eva stored all of the 1939 team's papers. She opens a vault and says something about how horrible it would have been if Hitler had gotten his hands on their bomb research. Well, considering how their bomb research ended, that might not have been such a bad thing. "There'd be Volkswagens everywhere!" Carter jokes. Meanwhile, Eva actually lived through the horror of WWII and probably doesn't think that's very funny. While they look through the research for something that can help save Zoe, Carter asks for exposition on why Eva came back to Eureka at all. She says she tried to move on, and did for a while, as women became more acceptable in the workplace and she was able to make something of herself. As a corporate fixer who fires people. Nice. She says she ended up being too good at her job, which got her the job at GD back in Eureka. When that happened, she decided it was time to find her old team. "I had to know," she says. At this point, Carter flips through a journal and finds a picture of Eva from 1939. It's got a name written on it, and that name isn't Eva Thorne. It's Mary Perkins. Nice of them to label the picture like that. "Jimmy was my brother," Eva sobs. Ah, of course. I assumed husband, but I was wrong. Sorry about that, Eva/Mary! That sucks for Jimmy, by the way, to have the same genes as his sister but she gets to live forever and he doesn't. Also, Frances Fisher is great in this scene. And the entire episode, really. A+ guest star casting, Eureka! She says if she knew Zoe would be exposed, she never would have opened the bunker again. "Don't worry about it. We're gonna help her," Carter says, sounding certain. Eva is not so much: "even if we find a cure, we can't get out of here." Carter says they will. He has faith in his team. And now he'll just need the thing he came down here to get in the first place: a bucketful of Element X. Eva says there's a whole storage pool of it in the cooling chamber. Way to leave that stuff lying around for seventy years, Team Perkins.