Spider-Man and the Green Goblin. Wolverine and Sabertooth. Captain America and the Red Skull. In comics, there are few dynamics more satisfying than classic archenemy pairings, and for the Agents of S.H.I.E.L.D., the go-to villains have always been Hydra. So it's no surprise that the very best moments from the second season Marvel Studios and ABC's Agents of S.H.I.E.L.D. have involved the multi-headed espionage organization. But it's not the simple fanboy satisfaction of seeing a hero's opposite that make that hold true. Week after week, the Hydra material on this show has been the most original, the scariest, the most affecting and the straight up most entertaining filmic elements of this corner of the Marvel Cinematic Universe. And it was no different across this week's "Frenemy of My Enemy."

After a few weeks spent getting deposed from his own organization, (former) Director Coulson is back to his original mission: saving Skye by taking the fight to Hydra. With limited resources and a ticking clock at hand, Coulson opts to track new Hydra heads Dr. List and Baron Strucker (who we'll likely never see on screen) with the help of S.H.I.E.L.D. defector/charming scumbag Grant Ward. From the opening showdown between Ward and Coulson's living weapon Deathlok on through Coulson's bluff that he'll use the T.A.H.I.T.I. process to erase the evil from the turncoat's brain as a path to reform, the scenes here crackle with energy and genuine drama. Even as Ward reveals to his face-changing lady love Agent 33 that their true plan remains to strike back at Hydra regardless of Coulson's needs, this thread makes us second-guess at every turn.

A plan is hatched. The former Hydra spy Bakshi -- now brainwashed into compliance with whatever Ward desires -- will meet with Dr. List with Deathlok in tow. The hope is that the meet will lead up the chain to Strucker (and evetually to Skye as Hydra continues to capture and experiment on super powered people). Add in Coulson ally Fitz's willingness to tear Ward's face off, Bakshi's "you can take Deathlok" audible and Hydra's own plan to hunt down a teleporting Inhuman in the midst of negotiations, and this haphazard mission becomes an off kilter fight where all sides struggle to stay one step ahead in the spy game.

Meanwhile back at S.H.I.E.L.D. HQ, the dust has settled and left Agent May full on board with the new management. After weeks of teasing, the show has left Coulson's formerly strongest confidant as his biggest doubter -- a fact underscored by May's quick breaking of Simmons' confidence in regards to the cube-shaped package of secret Nick Fury files the scientist helped Fitz escape with. Those shaky connections between our core characters aren't any more exciting than they've been in past weeks, but at least we get the sense that things will be moving to an endgame between Coulson and nuS.H.I.E.L.D. soon.

Last and certainly least, Skye continues to get jerked around by her Inhuman mother Jiaying. While this entire thread of the series has been a headline grabber both for its connection to an eventual Marvel movie franchise and for the way its aligned Skye's character with comic book counterpart Daisy Quake, so much of the Inhuman drama has been leaden. The secret city that house Jiaying's people has lacked in a real sense of scale or mystery, and Skye's family reunion has often been a slow-moving jumble of platitudes. This week, Jiaying insists on dumping former husband and certified psycho Cal Johnson somewhere on earth and moving on. When Skye points out the obvious solution would be to at least try to tell him that he should live elsewhere and trust that family dinners can continue at some later date, her mother shoots down the idea essentially "just 'cuz."

This impractical and frustrating storyline is saved in part by another wonderful turn from actor Kyle MacLachlan as Cal. The once and (possibly) future Dale Cooper has often attacked the S.H.I.E.L.D. material with a zeal unequaled by his fellow guest stars, and Cal and Skye's manic trip down memory lane when they're deposited in Milwaukee shows the kind of compelling character work the Inhuman scenes should have been delivering from day one. Even the forced "betrayal" of father by daughter when Inhuman Lincoln appears at Cal's office can't quite derail the energy MacLachlan brings to the scenes.

As with many, many episodes this season, Agents of S.H.I.E.L.D. ties these disparate story threads together by letting all the characters arrive at the same empty building at once. But the episode carries the "Spy Versus Spy" tension of its Hydra storyline in with fine form. Will Cal blow up at Lincoln and take things to a point of no return? Will the arriving Hydra forces capture any more powered people beyond Deathlok? Will Ward double cross Coulson or even his own Agent 33 when Skye crosses their path? Will Skye be able to trust Coulson when she sees who he's with? All these quandaries arrive in rapid succession and give the show some much needed intensity and doubt.

In the end, almost no one gets a resolution here, but with Deathlok and Lincoln captured and Coulson turning himself over to the late-arriving Mockingbird in order to pull the disparate S.H.I.E.L.D.s together to take the fight back to Hydra, the stories get complicated in compelling manner. Let's hope this war remains the focus moving forward.