[This is a review of Agents of S.H.I.E.L.D. season 4, episode 10. There will be SPOILERS.]

Season 4 of Agents of S.H.I.E.L.D. saw a major shift following the events of the winter finale. While Robbie Reyes, aka Ghost Rider (Gabriel Luna), played a big role in the series in the first half of season 4, the character was transported to another dimension along with his uncle Eli Morrow (Jose Zuniga), leaving S.H.I.E.L.D. down one Spirit of Vengeance. However, in the aftermath of their dealings with both Ghost Rider and Morrow, S.H.I.E.L.D. remained in possession of the Darkhold - which proved to be the motivator for Agents of S.H.I.E.L.D.'s newest major villain.

The winter premiere for Agents of S.H.I.E.L.D. season 4 saw a shift in focus from Ghost Rider to Dr. Holden Radcliffe's Life Model Decoys. Although it seemed the Darkhold had granted Aida (Mallory Jansen) consciousness, it was revealed in 'Broken promises' that Radcliffe was behind her robot apocalypse in an effort to obtain the Darkhold. Now, in this week's episode of Agents of S.H.I.E.L.D., the LMDs take a back seat again as S.H.I.E.L.D. deals with a major secret regarding Director Jeffrey Mace (Jason O'Mara).

In 'The Patriot' -- written by James C. Oliver  and Sharla Oliver and directed by Kevin Tancharoen -- an attempt to assassinate Director Mace leads to him, Coulson, and Mack being separated from their fellow S.H.I.E.L.D. agents. While Daisy and May attempt to track down the missing director, Simmons and Fitz are left at HQ to deal with General Talbot (Adrian Pasdar). Elsewhere, Radcliffe and Aida 2.0 have trouble containing the real May.

Project Patriot

Agents of SHIELD The Patriot Jeffrey Mace

On the whole, 'The Patriot' is a standalone episode that doesn't directly drive the main story of season 4, but does provide an important reveal that impacts the structure of the S.H.I.E.L.D. agency going forward. Although Aida's attack on S.H.I.E.L.D. HQ in the midseason premiere is addressed in 'The Patriot', much of the episode is focused on -- as the title suggests -- Jeffrey Mace, specifically how he acquired his Inhuman-like powers.

As such, the plot revolves around an attempt to assassinate Mace by ex-Hydra agents who have been hired by the Watchdogs. Mace, Coulson, and Mack are stranded in the West Virginia wilderness trying to reclaim a briefcase that was passed from Talbot to the director's right-hand man Burrows (Patrick Cavanaugh) earlier in the episode. Back at HQ, Simmons uncovers a file called Project Patriot and forces Talbot to come clean about what he, Mace, and Burrows have been hiding from the rest of S.H.I.E.L.D.

The secret is that Mace isn't an Inhuman, but instead derives his super-strength from a serum concocted by the U.S. government. As Mace explains to Coulson and Mack, it's calibrated specifically for his DNA, though he doesn't understand the science of it -- which generally ends badly within the Marvel Cinematic Universe with the exception of Steve Rogers aka Captain America (Chris Evans). Back at S.H.I.E.L.D. HQ, Simmons accuses General Talbot of bringing back the Erskine Program -- a reference to Captain America: The First Avenger's Super Soldier Serum created by Dr. Abraham Erskine (Stanley Tucci). Talbot goes deeper into the science, revealing they retooled the serum Daisy's father Calvin Zabo (Kyle MacLachlan) used to become Mister Hyde.

Agents of SHIELD The Patriot Phil Coulson Mack

The information dump about Mace's Patriot serum features a number of references to the larger MCU -- both within the history of Agents of S.H.I.E.L.D. and the organization's roots that date back to The First Avenger. It's a nice payoff for those viewers that have devotedly watched all the shows and movies set within the MCU, but the fallout from the revelation that Mace isn't an Inhuman is perhaps more important in terms of how Agents of S.H.I.E.L.D. will evolve from here. Since Mace has lied to the organization and the public as a whole, Coulson takes charge of S.H.I.E.L.D.'s operations, while Mace will stay on as the face of the agency.

While 'The Patriot' isn't necessarily the strongest episode of Agents of S.H.I.E.L.D. season 4, it does effectively reorganize the hierarchy of the organization, which will undoubtedly impact the series going forward. Still, with tensions running high in the U.S. and around the world between Inhumans the rest of the population, it remains to be seen whether S.H.I.E.L.D. employing an Inhuman imposter as the face of their agency will prove to be trouble.

Nevertheless, with Coulson back in charge, and the majority of his team having learned Mace's secret, Agents of S.H.I.E.L.D. is moving back toward a status quo of sorts. Daisy rejoined the team officially in the midseason premiere, and Coulson is back in charge of operations - albeit covertly, without technically demoting Director Mace. But, with the backstory of Jeffrey Mace/the Patriot now revealed, S.H.I.E.L.D. will likely soon learn things aren't actually as settled as they seem since the real May is being held by Radcliffe while a Life Model Decoy is impersonating the agent.

Radcliffe Bides His Time

Agents of SHIELD The Patriot May

While S.H.I.E.L.D. is largely focused on recovering their missing agents - and reeling from the revelation about Mace's powers - Radcliffe contends with holding May captive, which is more difficult than he believed. Fitz tells Radcliffe to lay low for a few days, explaining the scientist's absence from S.H.I.E.L.D. HQ during 'The Patriot'. But, when May wakes up unexpectedly, he discovers that keeping her in a relaxed state means giving the agent an opponent to combat (rather than forcing her to endure a hot stone massage).

All the while, Radcliffe discusses his programming of both Aida and LMD-May with Aida 2.0, talking through diminishing Aida's violence - particularly when it comes to killing humans. Furthermore, Radcliffe reveals that LMD-May isn't aware she's an android and, as showcased in the final moments of 'The Patriot', that could prove to be a problem for everyone as LMD-May inspects an injury to find metal plating beneath her skin.

On the whole, 'The Patriot' offered two important story developments in terms of LMD-May and Director Mace, wrapped up in a spy mission that is as fun and character driven as any other episode of Agents of S.H.I.E.L.D. It remains to be seen how the fallout from these revelations will play out in upcoming episodes, but it's clear that Agents of S.H.I.E.L.D. is continuing to develop the LMD storyline at a slow-burn pace (at least, in this episode) in addition to refocusing on Inhumans.

Next: Agents of SHIELD’s New Villain is Another Wolf in Sheep’s Clothing

Agents of S.H.I.E.L.D. season 4 continues with 'Wake Up' Tuesday January 24 at 10pm on ABC.