Marvel's Agents of S.H.I.E.L.D. had a rocky first season, but the turnaround it's made in the first three episodes of Season 2 has surprised even the fans who faithfully stuck around all of last year. Is it enough to save the show?

Even without the glut of comic book-based series on TV now, S.H.I.E.L.D. would be in trouble. Its second season premiere brought in half the viewers of the Season 1 premiere and the third episode posted a series low rating. If they can't convince viewers to come back soon, it will get buried under Arrow and Gotham and The Flash and all the other superhero stuff out there.

But there are plenty of reasons why viewers should come back. All of the setup S.H.I.E.L.D. did last year is paying off, and it's finally becoming the show everyone hoped it would be when it debuted in 2013.

For those who left the fold, here are five reasons why you should come back.



1. The Agents are no longer in control





Here's the single biggest change that has turned the show around: The agents of S.H.I.E.L.D. are now underdogs, which is what executive producer — and the man in charge of the creative direction of the Marvel Cinematic Universe — Joss Whedon does best. Now that S.H.I.E.L.D. no longer has the backing of Uncle Sam and are being hunted by the most dogged pursuer in all of comics (Hulk's nemesis Major Talbot played by Adrian Pasdar), we root for them inherently.

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2. The humor is lighter

Being underdogs also means the jokes hit harder. In the '80s, Schwarzenegger could say, "Stick around!" after nailing someone to a post with a machete and we'd laugh. But nowadays, it feels a little old-fashioned to spit out one-liners while holding an enormous gun.

What came across as cockiness before is self-effacing and endearing now. Hard to imagine Schwarzenegger saying, "We're lucky we still have our George Foreman Grill," with anything approaching the humor Agent Coulson (Clark Gregg) manages.



3. The darkness is darker





It began as far back as the middle of last season, when Skye was shot. She didn't die, but it introduced the idea that there was real danger for the characters. It reminded us that Joss Whedon is known for killing off beloved characters, even if they do sometimes come back (ahem, Agent Coulson).







This season begins with the death of Agent Hartley (Lucy Lawless), yes. But more importantly, we got to see the residual effects of last year's trauma. Everyone's a little more desperate, everyone's a little less trusting. Former Nick Fury artist and writer Jim Steranko criticized the show by saying it "had no menace, no tension." Well, Hydra brought all of that and more to the show.

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4. More spying! More super powers!

S.H.I.E.L.D. is set in the Marvel Cinematic Universe — in the same world as Hulk, Iron Man, and The Avengers — so it's perfectly reasonable to expect that we might see some Marvel superheroes, or at least some superpowers. The show is called Agents of S.H.I.E.L.D., so it's perfectly reasonable to expect that we'd see some spywork, some covert ops, some double-crossing.

When we got neither, fans became understandably angry. For them, it didn't matter that the show needed to create its own identity away from the established franchise characters. It didn't matter that they couldn't have moles or question anyone's loyalty for fear of exposing the Hydra angle early.