Last night's Agents of SHIELD was chock full of backstory, and we learned a ton about a handful of the show's villains and psychopaths. But the over-arching theme seemed to be revenge, and the ugly things that people do to get revenge for ancient injuries. Spoilers ahead...
"The Things We Bury" was a flashback-heavy episode, which filled in a ton of the details of how Reinhart, the Nazi scientist, became Whitehall, the Hydra leader. In a nutshell, Reinhart got hold of the Diviner (the object formerly known as the Obelisk) back in 1945, before he was captured by Agent Carter. And Whitehall basically forced a ton of prisoners to touch the object, until he found one who could survive contact with it: a woman, played by Dollhouse's Dichen Lachman.
And once Reinhart is in custody, we get to see a couple great scenes of him being interrogated by the soon-to-be-spun-off Agent Carter, who hears his wild stories of aliens and artifacts and then decides that he won't get the deluxe "Nazi scientist" package — instead, she'll just let him rot.
Years later, in 1989, Reinhart finally gets released from a SHIELD prison by some Hydra agents inside SHIELD, and he picks up where he left off — and lo and behold, he finds that same woman again, no older than she was in 1945. Reinhart dissects her, in a skin-crawlingly explicit sequence, and eventually manages to extract her powers of eternal youth and give them to himself.
That woman, apparently, was Skye's mother, and at the end of the episode we learn that Skye's dad (Kyle MacLachlan) found her mutilated body and vowed to find whoever had done this and inflict the same fate on him. Which means that his alliance with Whitehall is just a ploy, and he's actually just seeking revenge for his wife's death, and his separation from his infant daughter.
Also, MacLachlan's unnamed character provides a lot more backstory about the Diviner, on top of what Whitehall reveals in some of the flashbacks. Basically, blue creatures came down to Earth, and legends say they came to share gifts with us — but in fact, they were here to wipe out humanity except for a few chosen few, who could survive contact with the Diviner. (Were they Kree? Sure sounds like it.) And the Diviner is a key, that will allow a deserving person to get inside the city that Coulson was sketching.
So Skye's dad wants revenge on Whitehall, and judging from his crazy ramblings, he seems to think he'll only be reunited with Skye in the afterlife. And meanwhile, Whitehall is still pretty pissed at SHIELD for keeping him locked up for 44 years.
Grant's unfinished business
Meanwhile, Grant Ward tipped way over into the "psychopath" side of things with his behavior in this episode. Grant tracks down his brother, the Senator, who's planning a naughty weekend with a paramour, and captures him. Then Grant marches him out into the middle of nowhere and forces him to dig up the well where they once threw their other brother Thomas — which was either Grant's fault or Christian's, it's still unclear which.
Grant and Christian have lots of insane bickering, which gives us a window into their dysfunctional family life, and how good the Senator was at twisting everything around and getting inside Grant's head. (Which is another theme that comes up a lot in this episode, people who are good at manipulation and reality warping.) And then Grant holds his brother over the well, forcing him to admit that he was the one who instigated the whole "Tommy down the well" scenario, because Tommy was the only one their mom didn't torture.
And then you think that Grant is satisfied with his brother's confession, and that's all he wanted, and now everything's going to be all good — until you find out later that the Senator and his parents are all dead, in an apparent murder-suicide. And Grant used Christian's recorded confession to make it sound like he planned to kill his parents and himself. (It's entirely possible that Grant faked all this and Christian is alive, given that he was using this to get in with Whitehall.)
In any case, by the end of the episode, Grant has apparently joined Whitehall's team, replacing Bakshi, whom Grant handed over to SHIELD last week. And Grant does appear to be a great fit for Whitehall's inner circle, given that they're both psychos who can hold onto a grudge or an obsession for decades. (Although I'm guessing Grant still wants to "prove" himself to Coulson, by infiltrating Hydra.) The final moment with Ward, Whitehall and Skye's dad all smiling at each other is just endlessly creepy.
Coulson's obsessions are actually paying off
Meanwhile, Coulson is being a good leader again, after having seriously gone off the deep end during the whole "carving on the wall" business. Early in the episode, Mack expresses some reservations to Lance Hunter about Coulson's erratic behavior of late, but then the rest of the episode shows a Coulson who's completely on top of things, even though he seems unpredictable to say the least.
Coulson has a plan to find the mysterious alien city that the Diviner opens up, so he can be at the finish line when Whitehall finishes his race, instead of racing against him. And his plan involves going to Hawaii, where there's a big satellite relay station, and using a button and a watch to induce an EMP, so the less secure backup station in Australia will go online — at which point, Fitz can tap in to the system and find the hidden city.
Coulson explains none of this to his people, instead giving them confusing missions regarding the button and the watch, and badgering Fitz to get better at installing a transmitter in under six minutes. (And they also pick up Coulson's dry-cleaning.) But in the end, his wacky scheme pans out, and Fitz actually performs well under pressure.
And when the mission goes sideways, as they always do, Coulson helps to save Tripp's life. They're attacked by Hydra goons, and Tripp gets shot. So Coulson is forced to team up with Skye's crazy dad, who sort of saves Tripp and sort of nicks an artery to make things worse — but then gives Coulson magic coagulants, so he can save Tripp while Skye's dad gets away.
Coulson is about to tell Skye all about meeting her wacky dad, but then their satellite search pans out, and they locate the city that Coulson and the others were drawing for so long.
Lance and Bobbi
The least successful part of the episode has to do with Lance and Bobbi working out their ex-marital issues while Bobbi is interrogating the newly captured Hydra agent Bakshi. Bobbi is trying to get under Bakshi's skin, using all her manipulative tricks, and this all reminds Lance of their marriage.
Plus Bakshi tries to throw her off the scent by alluding to the terrible things that Bobbi did to prove herself loyal to Hydra when she was undercover — which bothers Lance more than you think it would, given that he's been in this world for a long time.
In the end, Bobbi picks up on a clue that Bakshi drops inadvertently, and that's how the team figures out that Whitehall used to be Reinhart and that he's somehow immortal-ish. But Bakshi kills himself using a cyanide capsule in his cheekbone, and Lance suspects that Bobbi goaded Bakshi into suicide so he wouldn't blow the whistle on her.
All of this leads to a big relationship shout-fest, in which Lance says he'll never trust his ex-wife, but he'll never stop wanting to. And then they have sex.
All of which goes to show — everybody has unfinished business and old hurts and resentments. But where some people are driven to spend decades hunting other people down, or to kidnap and murder their family members, other people are able to rise above and have good old-fashioned post-break-up sex. There's a moral there somewhere.