Since the premiere of WandaVision in 2021, MCU shows have stuck to a formula: Take a genre, but throw a Marvel hero at it. That's how we get coming-of-age stories like Ms. Marvel, procedural sitcoms like She-Hulk: Attorney at Law, and psychological thrillers like Moon Knight. Marvel's latest, the Nick Fury-centric Secret Invasion, continues that pattern with its deep ties to spy thrillers.

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Secret Invasion certainly isn't the first time the MCU has dipped its toes into the spy genre. For that, look no further than films like Captain America: The Winter Soldier and Black Widow, or TV series The Falcon and the Winter Soldier. While these titles kicked off the MCU's foray into spy territory, Secret Invasion is the project that engages the most with the genre. The first two episodes deliver exciting set pieces, intriguing political espionage, and a healthy dose of double agent paranoia courtesy of a shapeshifting foe. It may be a promising start, but given how most MCU shows abandon genre specificity in favor of One Big Final Battle, there's a worrying chance that Secret Invasion will drift away from what makes it unique in favor of more Marvel homogeneity.

What's Secret Invasion about?

Kingsley Ben-Adir in "Secret Invasion." Credit: Courtesy of Marvel Studios

To fully understand the plot of Secret Invasion, you must cast your mind back to Captain Marvel. There, we encountered the Skrulls, an alien race who can assume anyone's form and mannerisms. As we learned in Captain Marvel, they're refugees displaced by a war with the Kree. Nick Fury (Samuel L. Jackson) promised to help the Skrulls find a new home, allying himself with Skrull Talos (Ben Mendelsohn) in the process.

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However, it's now been decades since the events of Captain Marvel, and Fury has yet to honor that promise. (Assembling the Avengers and getting Thanos-snapped out of existence will do that to you.) Tired of waiting, a hostile Skrull faction has infiltrated humanity, covertly taking over major positions of power and staging international conflicts. The goal? Wipe out humans entirely, and rebuild Skrull civilization in their place.

To say this is a major threat would be an understatement, and it's enough to get Nick Fury to leave his space station vacation and come back to Earth. There, he reunites with Talos and Maria Hill (Cobie Smulders) to put a stop to the rebel Skrulls — including their leader Gravik (Kingsley Ben-Adir) — once and for all.

Secret Invasion is Marvel in spy mode.

Olivia Colman in "Secret Invasion." Credit: Courtesy of Marvel Studios

Nick Fury and Maria Hill don't have the skillsets of the Avengers or other MCU characters, so Secret Invasion pulls its thrills more from politicking and undercover espionage than from superpowers or flashy armor. Meetings in back rooms, secret alliances, coded messages... these are Secret Invasion's playing field.

However, that playing field is wildly unbalanced given the one major superpower at the forefront of Secret Invasion: the Skrulls' shapeshifting ability. Often, the face of a character you've assumed to be human will ripple and morph back into a reptilian alien form, revealing that — gasp! — they've been a Skrull this whole time. It's a neat storytelling device, one that sows paranoia right from Secret Invasion's first scene and provides some genuinely surprising payoffs. Could an overuse of "gotcha" reveals grow tiring down the line? Potentially. But for the first two episodes, at least, they remain a fun Marvel twist on the trope of the double agent.

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Besides the double agent shenanigans, there are several other elements of Secret Invasion that feel as if they've been pulled right from a spy thriller — a Cold War thriller, even. Yes, this is a series that takes place in the present day, but Secret Invasion uses current tensions between the United States and Russia as a backdrop for its alien conflict. For example, quite a bit of these first two episodes takes place in Moscow, the extremist Skrulls have set up shop in an abandoned nuclear plant, and concerns about stolen weapons kicking off World War III propel the show's initial action. The U.S.-Russia aspects of the show only snowball from there.

With all these nods to real-world events, it's hard not to wish Secret Invasion would dive deeper into its own allegories and explorations of social issues. The Skrulls' refugee hardships motivate Gravik and his companions, including Talos' daughter G'iah (Emilia Clarke), but Secret Invasion pivots immediately into their villainous schemes instead of situating us in their experiences. Luckily, Ben-Adir proves a steely adversary whose devotion to the Skrull cause speaks volumes about his past — if only Secret Invasion could match that with its plot.

However, there's lots of fun to be had elsewhere in Secret Invasion. Jackson continues to bring bucketloads of charisma to the role of Nick Fury, although this iteration is a little more haggard and strung-out after the Blip. His chemistry with Mendelsohn (also a delight) is downright sizzling, to the point that I wondered, "Is Talos/Fury the next big Marvel relationship?" (Based on Marvel's prior track records with queer coding characters, I'm going to guess not.)

But even though we've known Nick Fury for over a decade, and even though Secret Invasion features full-on aliens, it's Olivia Colman who absolutely steals the show. As MI6 agent Sonya Falsworth, Colman is instantly charming and just the right amount of icy. Plus, Sonya's a whiz at torture, allowing Colman to tap into some darkly fun Bond villain energy — although for the time being she's still a friend of Fury's. Given just how quickly allegiances in spy thrillers can change, though, there's no guarantee they'll still be allies by the end of the show.

The unpredictability when it comes to spy allegiances is one of the joys of the espionage genre. However, some of that edge is dulled when it's paired with the predictability of a Marvel show. Time and time again, these series promise us an intriguing start, only to finish the season with fights that begin to blur into one another. Secret Invasion's spy leanings would favor a more tense, contained story, especially following its grounded fights and chase sequences. However, some forced references to the Avengers and hints at Gravik's plans suggest that this show may still be too stuck in the MCU formula to fully spread its wings.

Here's hoping that Secret Invasion sticks to the course it has set itself in its first two episodes, though. As a spy show and an MCU show, it's off to a solid start. It's only when it starts to lean too hard on the latter that it risks disappointing.

Secret Invasion premieres June 21 on Disney+, with new episodes weekly.