It also stars Eka Darville, Elden Henson, Jessica Henwick, Simone Missick, Ramón Rodríguez, Rachael Taylor, Deborah Ann Woll, Élodie Yung, Rosario Dawson, and Scott Glenn, all also returning from previous series, as well as Sigourney Weaver.

[45] In October 2013, Deadline Hollywood reported that Marvel Television was preparing four drama series and a miniseries, totaling 60 episodes, to present to video on demand services and cable providers, with Netflix, Amazon, and WGN America expressing interest.

[46] A few weeks later, it was announced that Marvel Television and ABC Studios would provide Netflix with live action series centered around Daredevil, Jessica Jones, Luke Cage, and Iron Fist, leading up to a miniseries based on the Defenders.

Daredevil creator Drew Goddard also serves as an executive producer on the miniseries,[49] along with Karim Zreik, Cindy Holland, Allie Goss, Alison Engel, Kris Henigman, Alan Fine, Stan Lee, Joe Quesada, Jim Chory, and Marvel Television head Jeph Loeb.

[57] Scenes in the early episodes were created to feel like the "most optimal versions" of each individual series, using visual and sonic elements from each that are slowly combined as the miniseries goes on.

[57] Loeb did not want a villain like the aliens from The Avengers because these are "street level heroes [who] come from a very real place",[11] but each of the Defenders has been shown to be "really powerful" in their individual series and the antagonist would have to prove a challenge for the four of them together.

[18] Ramón Rodríguez also reprises his Iron Fist role as Bakuto,[21] while Rosario Dawson returns as Claire Temple from all of the previous Marvel Netflix series.

[21] Other actors reprising their roles for the miniseries include Daredevil's Wai Ching Ho as Madame Gao,[32] Peter McRobbie as Father Paul Lantom,[36] Amy Rutberg as Marci Stahl,[40] and Susan Varon as Josie;[41] Jessica Jones' Carrie-Anne Moss as Jeri Hogarth and Nichole Yannetty as Nicole;[16][42] and Rob Morgan as Turk Barrett, from previous Marvel Netflix series.

[71] For Cage's scenes, Lloyd was inspired by Harris Savides work on American Gangster (2007), and for Iron Fist he looked to Wong Kar-wai's The Grandmaster (2013).

[73] Clarkson and Lloyd also learned the technical requirements for depicting the character's Iron Fist based on the process used by that series' crew, along with how the effect of Cage's abilities were created.

[78][79] For Alexandra and the Hand, the executive producers suggested the color white as a repurposing of the phrase "the light at the end of the tunnel" given the group are immortal supervillains.

[80] Because it would look out of place on the streets of New York, Maslansky also designed a coat for her to cover this up that was inspired by The French Lieutenant's Woman (1981) and The Matrix (1999), and meant to appeal to Alexandra's taste in clothing.

[89][71] Due to the production demands, he brought his long-time second unit cinematography collaborator Jim McMillan onto the miniseries to help balance the workload for when episodes were filming simultaneously.

[71] Additional filming locations for the miniseries included Upper West Side, Hell's Kitchen, and Williamsburg, Brooklyn,[90] Stapleton, Staten Island,[91] St. Nicholas Park, the lobby and exterior of Atelier ("Midland Circle"), the Central Park Mall, the rooftop gardens at Rockefeller Center, the Downtown Manhattan Heliport, 240 Centre Street in Manhattan, the Appel Room at Time Warner Center, and the New York City Municipal Archives.

[73] Particularly difficult sequences for Clarkson to shoot included the opening of the miniseries, which features a sword fight in a wet tunnel with water on set causing issues for the crew; the introduction of Matt Murdock in a courtroom, which was shot in a single take as a reference to the single take fight sequences that the character has in his series; and the earthquake scene, which combined practical effects such as "pulling all these things with strings and making everything move" with planning for visual effects and could have come across as "hokey" if done wrong.

Additionally, he noted the different stunt team and directors for The Defenders allowed for improvements to be made, calling the choreography of the miniseries' action "a lot slicker" and more cohesive.

[98] Paesano felt "there was more license to push the envelope and lean a bit more into the orchestral colors" of each character since they were "dealing with outright superheroes that [their] audience is familiar with".

[27] In April 2017, the series' release date was revealed via a teaser trailer designed to look like security footage showing the four Defenders inside a Midland Circle elevator.

[105] Dave Lewis of the Los Angeles Times felt having the security footage teaser end on the timecode 08:18:20:17, was "a fun way to indicate the show's release date".

Nicole Sobon of Comic Book Resources felt releasing these this way was "a smart marketing move by both Marvel and Netflix, as over the course of the years, the Twitter accounts [for each series] have managed to drive in plenty of fan interaction by their 'conversations' between the characters".

[108] Cox, Ritter, Colter, Jones, and additional stars of the miniseries appeared at the 2017 San Diego Comic-Con to promote the series,[109] where the first episode was also screened.

Jumpshot, which "analyzes anonymized click-stream data from a panel of more than 100 million internet consumers", looked at the viewing behavior and activity of the company's U.S. members, factoring in the relative number of U.S. Netflix viewers who watched at least one episode of the season.

"[120] Nielsen Media Research, which tracks streaming viewership on U.S. television screens, reported that The Defenders garnered 2.8 million viewers on the day of its release.

The site's critical consensus reads, "Marvel's The Defenders further develops well-known characters in an action-packed arc whose payoff packs more than enough of a punch to offset its flaws.

Tracy Brown of the Los Angeles Times noted after "a quick refresher on where each hero's solo story left off ... there is forward progress in the narratives for each" of the Defenders, despite them not interacting in the episode.

[129] Polygon's Julia Alexander was "stupidly excited to binge the rest of the season" after seeing the first episode, praising the "intriguing" Alexandra and her relationship with Elektra, as well as the miniseries' efforts to focus on the individual identities of the Defenders.

She did criticize the amount of exposition, the unoriginal story, and the "over-the-top" villains, but felt that "the good of The Defenders far outweighs the bad ... it's all a canvas to showcase Matt, Jessica, Luke, and Danny coming together [to be] more entertaining".

She felt some of the solo series issues such as pacing and narrative choices were still present, but there were still elements to enjoy including Jessica Jones and the banter among the heroes.

Lawler felt Rand was the "undeniable handicap" of the series, having hoped that "The Defenders would shy away from Danny and his petulance, but unfortunately, Iron Fist is integral to the larger plot".

[152] With Echo's release, all of the Netflix series were retroactively added to the MCU Disney+ timeline, with The Defenders placed between the films Ant-Man (2015) and Captain America: Civil War (2016).