The show's third season stars Karl Urban, Jack Quaid, Antony Starr, Erin Moriarty, Dominique McElligott, Jessie T. Usher, Laz Alonso, Chace Crawford, Tomer Capone, Karen Fukuhara, Nathan Mitchell, Colby Minifie, and Claudia Doumit returning from prior seasons, with Jensen Ackles joining the cast.

Concurrently, Homelander's mental stability begins to deteriorate as Vought attempts to restrict his power while other Seven members, such as Annie January / Starlight (Moriarty) and Queen Maeve (McElligott), assist the Boys in their plots against him.

The season received positive reviews with praise towards its action sequences, social commentary, visual effects, character development, story, and performances (particularly Urban, Starr, Alonso, and Ackles).

[4] Charlize Theron, Billy Zane, Seth Rogen, Jaz Sinclair, Patton Oswalt, Josh Gad, Ashton Kutcher, Mila Kunis, Elizabeth Banks, Kumail Nanjiani, Aisha Tyler, and Rose Byrne made cameo appearances, with Theron making a cameo appearance as Stormfront in the fictional film within the series Dawn of the Seven in the episode "Payback",[27][28] Zane as portraying Alastair Adana in another fictional film within the series Not Without My Dolphin while Sinclair ahead of starring in the spinoff series Gen V, appears in a photograph as Marie Moreau for the episode "The Only Man in the Sky",[29][30] and Rogen portraying a SupePorn.com patron "SirCumsALot779" in the episode "The Last Time to Look on This World of Lies".

[32][33][34] On July 23, 2020, the series was renewed for a third season at the aftershow hosted by Aisha Tyler for the 2020 San Diego Comic-Con@Home, less than two months before the second-season premiere.

[35][36] Showrunner Eric Kripke revealed that he was already working with the scripts for the season in October, hoping to have them finished and start production in early 2021 as long as the condition of the COVID-19 pandemic improved.

[37][38][39] Due to the restrictions of live-action productions during the pandemic, Kripke and the producers have the idea of keeping the fans of the series engaged while they waited for the release of the third season, leading to the anthology animated spin-off miniseries The Boys Presents: Diabolical.

[45] He detailed over how the toxic masculinity was an ongoing issue that as by today continues affecting the lives of a lot of men, with many of them being targeted for not being considered ‘manly’ enough and over how this becomes very destructive to the society and organizations.

This was the main reason of Soldier Boy being introduced as he represents the embodiment of the toxic masculinity which is an issue that the world still faces thanks to the older generations.

[46] Actor Jensen Ackles explained that the character is someone who seeks power with by following a "macho illusion" that actually doesn't exist and over how in the States that myth ended up growing through generations that affected men that could not live it up to it.

"[55][56] Many of the changes were applied to Homelander a threat just as he is finally starting to take control of Vought, but Kripke wanted to ensure that it was someone that the character has never faced before with someone that has the same strength as him and could actually fight him, for which he considered Soldier Boy to be the best match.

"[61][62] Kripke explained that the changes were mostly done to get a deeper exploration at Vought's history by also exproing the past of each member of the teams, so the writers are allowed to shed the light on the show's present.

[68][69] In August 2020, it was announced that Jensen Ackles would be joining the show as Soldier Boy, promising that "the character would bring so much humor, pathos, and danger to the role.

With that pedigree we dove headfirst into baking in an all-American quality grounded in a military soldier's practicality with a heavy dose of old school cowboy swagger.

"[71][72][73] In October 2020, it was announced that Claudia Doumit and Colby Minifie would reprise their roles as Victoria Newman and Ashley Barrett respectively, with both being promoted to series regulars.

[74] That June, Miles Gaston Villanueva, Sean Patrick Flannery, Nick Wechsler and Laurie Holden were cast as Supersonic, Gunpowder, Blue Hawk, and Crimson Countess respectively.

[79][80] Paul Reiser also makes an appearance in the series as The Legend, a spoof of legendary screenwriter and producer Robert Evans whereas his comics counterpart was based on Stan Lee.

[84][85] Due to the COVID-19 pandemic that led to the delay and cancellation of multiple television series, Kripke was worried that the COVID-19 could endanger the filming for the season causing conflicts with filming schedules, guest stars, and how can it work with the story, since he did was determined to keep the same quality levels found in the previous seasons as safety protocols for the pandemic were applied, for which he considered to be the toughest and most complicated production he has faced.

[105][106] Lennertz delved further for the creation of these new songs by request of Kripke, creating a fictional in-universe musical boyband named Super-Sweet for which Villanueva's character Supersonic is the leader.

Both cover songs are respectively featured in the fourth ("Glorious Five-Year Plan") and seventh episodes ("Here Comes a Candle to Light You to Bed"), and also the two are performed by Jensen Ackles.

[130][131] Alexandra Del Rosario from Deadline said that the trailer brought suspense by teasing what is coming to the season while also offering "plenty of gore in store for The Boys fans".

[133] Indie Wire's Samantha Bergerson deemed that the teaser offers a "bevy of blood, guts, and tears as humans and supes alike battle it out", even if it doesn't include any dialogue.

[139] Digital Spy's Shaun Wren deemed the trailer to be "packed with new heroes, gruesome scenes and a proper introduction to Jensen Ackles' original superhero Soldier Boy", and was excited to see the new developments that have taken during the time jump from the second to third season.

[140] By mid-2021, Amazon created Vought International account across social media platforms such as YouTube, Facebook, Instagram, Twitter, and TikTok as part of their strategy for an innovative viral marketing campaign of The Boys.

Most of the published posts are faux news, music videos, announcements, commercials, and propaganda regarding Vought and the Seven with many of the commentaries being written like if it were from the people that actually lived in the fictional world.

[141] Due to the satirical nature of the series, the marketing campaign approach is intended to touch into the "corporate greed and corruption and how celebrity is weaponized to mask accountability", while some of the posts also portray the in-universe consequences of the events occurred through the series, intending to make critique towards capitalism as well as the social and political issues surrounding America in modern times, while also making parodies of not only the superhero industry but also the studios behind it such as Disney.

[157][158] The following day, the in-universe outtakes of Soldier Boy were published revealing the true colors of the character as a hypocritical short-tempered, foul-mouthed, alcoholic, and drug-addicted superhero.

The website's critical consensus reads, "Managing to up the ante on what was already one of television's most audacious satires, The Boys' third season is both bracingly visceral and wickedly smart.

"[171] Jennifer Bisset from CNET praised the show for its meta humor and character development and commented: "Every episode guarantees early Game of Thrones level fornication and bloodshed – albeit the gory bits have a cartoonish CGI sheen.

Fortunately, The Boys feels like a work made by people who have plenty of ammunition for both sides of the aisle, as no ideology has a monopoly on craving power — or on worshiping those who amass it.