In this series, the founding members of the Defenders are Daredevil, Jessica Jones, Luke Cage and Iron Fist. In the comics, the Defenders were formed by The Incredible Hulk, Doctor Strange, Silver Surfer, and Namor the Sub-Mariner.
In the first few episodes, the production uses colored light to great effect to separate out each individual Defender story. Each scene involving Daredevil has a hint of red. Jessica Jones is lit with purple. Iron Fist with green and Luke Cage is lit in shades of yellow. As the series progresses and the Defenders become aligned, the four colors eventually turn into more neutral whites and blues.
When Matt and Jessica are leaving the police station, a photo of Stan Lee can be seen on a wall in the background.
The IP address hidden in the first teaser trailer leads to a site with information about The Defenders.
In the Marvel Comics, the Defenders have a constantly shifting roster. As of 2025, the Marvel Cinematic Universe has 28 characters who have appeared in the Defenders:
- Dr. Strange, the Incredible Hulk, Captain America, Hawkeye, Falcon, Spider-Man, Captain Marvel and Loki (who have their own film/TV series)
- Yondu, Drax the Destroyer, and Howard the Duck (debuting in Guardians of the Galaxy (2014))
- Scarlet Witch and the Vision (debuting in Avengers: Age of Ultron (2015))
- Hank Pym and Scott Lang (Ant-Man) (debuting in Ant-Man (2015)) and Janet van Dyne (Wasp) (debuting in Ant-Man and the Wasp (2018))
- Daredevil, Luke Cage, and Iron Fist (who all got their own series)
- Patsy Walker (Hellcat) (appearing in Jessica Jones (2015))
- Valkyrie (debuting in Thor: Ragnarok (2017))
- John Walker (US Agent) (debuting in The Falcon and the Winter Soldier (2021))
- She-Hulk (debuting in She-Hulk: Attorney at Law (2022)).
- Hercules (debuting in Thor: Love and Thunder (2022))
- Clea and America Chavez (debuting in Doctor Strange in the Multiverse of Madness (2022))
- Elsa Bloodstone (debuting in Werewolf by Night (2022))
- Namor the Sub-Mariner (debuting in Black Panther: Wakanda Forever (2022))
- The Silver Surfer (debuting in The Fantastic Four: First Steps (2025)).