The two-hour “Marvel’s Agents of SHIELD” finale certainly didn’t scrimp on action, capping a season in which the ABC series continued to do a synergistic tap dance – operating within the confines of the broader Marvel universe – while pursuing an extended plot involving the fate of Skye (Chloe Bennett), whose origin story became a season-long theme. After a rocky first season, the program benefited from expanding its cast, the shrewd use of guest stars and an embrace of serialized storytelling. While it’s clear “SHIELD” won’t be a major hit – the numbers, in fact, are fairly mediocre – it has settled into a respectable holding pattern.

None of that appeared certain after season one, which arrived amid inflated expectations and hoopla; at times felt like a run-in with the enhanced villain of the week; and finally had to deal with a “Captain America: The Winter Soldier” tie-in that essentially blew up SHIELD – and by extension, the show.

Skye’s metamorphosis, and the battle with one-time team member/Hydra mole Ward (Brett Dalton), provided a link to those beginnings while moving the narrative forward. Nor did it hurt having actors like Edward James Olmos, Blair Underwood and Kyle MacLachlan turning up in recurring roles, even if the last of them occasionally seemed to be auditioning for a remake of “The Shining.”

In the finale (and SPOILER ALERT if you haven’t watched), SHIELD – after a period characterized by what amounted to “Who can you trust?” intramural politics – came together to face an external threat, the Inhumans. Under the leadership of Skye’s mother (Dichen Lachman), the gifted invaders mounted a full-scale assault. Meanwhile, Agents May (Ming-Na Wen) and Hunter (Nick Blood) sought to rescue Mockingbird (Adrianne Palicki) from Ward.

By any measure, there was a lot going on, creating an excuse not only for plenty of butt-kicking fights but some playful dialogue, such as Mack (Henry Simmons) telling Skye, “And I thought my mom was bad when she started watching Fox News.” Super-villains are one thing, but weathering irate letters from the Media Research Center really requires guts.

Although the forces of SHIELD emerged victorious, Ward remained at large and determined to strike back, while Coulson (Clark Gregg) cited plans to assemble a team of agents with powers. If nothing else, that should stretch the special-effects budget, while offering a variety of directions and threats to pursue going forward.

At times, “SHIELD” still feels like a poker chip in a larger game, from the crossovers to the Marvel movies (having played a minor role in setting the stage for “Avengers: Age of Ultron”) to its more elaborate part in introducing the Inhumans in advance of a planned movie several years from now. Indeed, one can make a case that the benefits associated with being part of the Marvel machinery haven’t consistently manifested themselves in the show either from a ratings or a creative standpoint, and that talk of spinoffs and the somewhat disappointing “Agent Carter” have added to the degree of difficulty in establishing a new series.

When the show premiered, a TV executive unaffiliated with Marvel or ABC quipped that “SHIELD” was a limited construct, wryly suggesting that its appeal could be summarized as, “You see that guy? He’s met Iron Man.” Under showrunners Jed Whedon and Maurissa Tancharoen, the series has proved more resourceful than that – including unexpected surprises, like Coulson getting his hand whacked off.

Now two seasons in, the result is a show that’s generally fun but not exactly super – except, inevitably, in the eyes of a small if inordinately vocal audience, which tends to magnify its media footprint. Just as Skye had to master harnessing her powers, though, “Agents of SHIELD” is experiencing its own learning curve, which includes the more mundane, sometimes thankless task of serving as a weekly ambassador for the Marvel brand.