Agent Jemma Simmons smiles as she struts into her new job. But the deceptively upbeat song that scored the cold open of Marvel's Agents of S.H.I.E.L.D. last night – "God Help the Girl" by the eponymous Belle & Sebastian side project – hinted a more sinister side to her new life. Jemma is a Hydra lab tech. And while the twist of that premise could be predictable, the confidence with which the series told it was like singing.

If there's one thing the show is displaying this early in the second season, it's swagger. With the "Making Friends and Influencing People" episode (written by Monica Owusu-Breen) Agents opened up the complexities of the new S.H.I.E.L.D./Hydra dynamic with style.

Appropriate for a spy series, the tension that runs across the episode is a game of "Whom do you trust?" Even as the possibility of Jemma going over to the villainous organization is revealed as an undercover op, plenty of other double-agent seeds get sewn through the story.

First and foremost, there's immortal Hydra heavy Daniel Whitehall (aka Kraken to comic readers), who takes a leisurely pace at brainwashing the rogue S.H.I.E.L.D. agent he can't recruit to his cause. The primary antagonist for this stretch of the season is played like a murderous Roger Sterling by actor Reed Diamond for an effectively creepy introduction to Hydra's "strength through submission" world view. When he asks, "Are you ready to comply?" to faltering S.H.I.E.L.D. Agent 33, you almost want to say "Yes."

Meanwhile, back at S.H.I.E.L.D.'s Playground HQ, captured turncoat Agent Ward pushes beyond the role of bearded Basil Exposition as he delivers new info to Skye. In an episode full of shifting allegiances, Ward seems the only person telling the whole truth. You see it when he admits that, despite Hydra's brainwashing powers (named after Captain America villain Doctor Faustus, to boot), he committed every crime without coercion. And you see it even more when his life hangs in the hands of Agent Fitz – the man Ward himself handicapped – yet he jumps with genuine concern upon realizing the team is walking into a trap.

But the trust issues that hold the most sway over the hour belong to Donnie Gill, the former S.H.I.E.L.D. Academy student turned de facto Iceman in Season 1. Donnie has been on the run since breaking out of S.H.I.E.L.D.'s facility for "gifted" individuals, and he trusts neither S.H.I.E.L.D. nor Hydra to bring him peace. Ward's realization that Gill had already been turned to Hydra via the Faustus method was an honest to goodness twist right when the episode needed it. It turned the teen on the run trope into a ticking time bomb set to destroy Jemma's cover if not her life.

Even as those dramatic wheels turned, the episode never lost a sense of fun. New S.H.I.E.L.D. mechanic Mack remains a welcome foil to Fitz's tortured state of mind (and thus #FitzMack was born). Clark Gregg's Director Coulson is as affable on screen as he ever was in a big-budget movie. And even May and Skye's moments of understanding bring a sense of calm to tense moments.

Ultimately, the struggle to turn Gill to S.H.I.E.L.D. before Hydra unlocks his programming turns into a much more important piece of the show's overall puzzle. While Coulson's agents don't save Gill, his sacrifice proves Simmons' place as a loyal Hydra soldier (for now). Watching the lighthearted fan favorite live under the threat of Whitehall's Clockwork Orange tendencies should make for some terrific twists even as bigger mysteries (like Skye's father) wait for later this year.