Robert Downey Jr's Relationship With Every Avengers Co-Star Explained

The core six members of The Avengers became pop culture icons in 2012, and each has a different, albeit heartwarming friendship with the actor who helped kick off the MCU: Robert Downey Jr. Compared to the MCU’s ongoing Phase 4 of blockbuster superhero movies, Iron Man was small, quaint, and character-driven affair, with much of its dialogue improvised by Robert Downey Jr and his co-stars. Yet Iron Man helped turn Marvel Studios’ ambitious hopes of a shared Marvel movie universe into a reality that was fulfilled by The Avengers four years later. Throughout the first Phase of the MCU, the franchise gradually built its roster until the all-star team formed in 2012, with the six actors’ palpable chemistry being one of The Avengers' strongest elements.

The Avengers was an overnight sensation, serving as both a payoff to five other movies and proof that a comic book-style shared continuity can work on film. The Avengers’ success not only led to two more phases of MCU films (including three more Avengers movies), but it also made the six founding team members household names. Naturally, given their phenomenal onscreen chemistry, it’s unsurprising that all six cast members seem to be good friends off-set, offering words of encouragement, mild pranks, and social media shout-outs to each other - proving that their chemistry is as strong off-camera as it is in the MCU films.

This same chemistry applies to the original Avengers stars and the superhero team’s new members since the MCU team’s roster changes rather frequently as it did in the mainstream Marvel Comics universe. Avengers: Infinity War and Avengers: Endgame both brought nearly the entire MCU together in their final conflict against Thanos, leading to Robert Downey Jr and his Avengers co-stars demonstrating similar chemistry with the Guardians of the Galaxy cast. Following the end of the MCU’s Infinity Saga in Avengers: Endgame, Robert Downey Jr has moved on from his iconic Tony Stark role, yet the interviews, social media posts, and cast events from the MCU’s first three phases prove that he has a strong friendship with his core Avengers co-stars as well as other MCU actors who joined the roster later.

Chris Evans

Robert Downey Jr’s friendship with Chris Evans is one of the best-documented relationships between MCU stars. From heartwarming birthday wishes and comparisons to other famous Disney duos on Twitter to a humorous video in which the two prepare to brawl over a doughnut, Robert Downey Jr and Chris Evans have repeatedly proven that while their onscreen personas have a rather tumultuous friendship, they couldn’t be more appreciative of each other. Following Endgame, Chris Evans voiced his belief that Downey Jr is irreplaceable as Tony Stark, and The Story of Marvel Studios: The Making of the Marvel Cinematic Universe reveals that Robert Downey Jr ultimately convinced Chris Evans to audition for the role of Steve Rogers.

Jeremy Renner

Robert Downey Jr also enjoys a friendship with Avengers co-star Jeremy Renner. While promoting the Disney+ series Hawkeye, Renner spoke of his friendship with Downey Jr, describing him as being as much a mentor as a friend. Just as Robert Downey Jr helped initiate the MCU itself in Iron Man, he helped ease Jeremy Renner into the superhero role of Hawkeye for multiple MCU phases, which helped establish the crowd-pleasing chemistry of the original six Avengers members.

Scarlett Johansson

Robert Downey Jr and Scarlett Johansson have had perhaps the longest onscreen history in the MCU since the latter debuted in Iron Man 2, establishing the canon history between Iron Man and Black Widow. The two were great friends off of the set, as were the rest of the founding six Avengers members, with Downey Jr notably sending Johansson a congratulatory video message when she received her American Cinematheque Award. In a hilariously profane message, which felt rather similar to his onscreen persona of Tony Stark, Downey Jr sarcastically pokes fun at his Avengers co-star (and himself) in a way that only a close friend could.

Chris Hemsworth

While the original Avengers team actors all became friends by the time the 2012 film hit theaters, Robert Downey Jr and Chris Hemsworth got off to a strange start. According to Jeremy Renner, Downey Jr was taken aback by Hemsworth’s charisma and jokingly suggested that they break his knees as a remedy. Downey Jr is, of course, known for having a risqué sense of humor, and the two soon became friends, despite Downey Jr’s jokes.

Mark Ruffalo

Bruce Banner Tells Tony Stark About Thanos Avenges Infinity War

Robert Downey Jr and Mark Ruffalo are known for being particularly close, embodying their brainiac friendship both onscreen and in reality. As with Chris Evans and Jeremy Renner, Robert Downey Jr took on something of a mentor role for Mark Ruffalo, convincing him to accept the role of Bruce Banner when Ruffalo was unsure about taking the part in 2011. The two were friends well before they became Avengers co-stars, and Ruffalo once described Downey Jr as feeling like an older sibling to him.

Robert Downey Jr’s Other Avengers Co-Stars

Avengers Infinity War and Avengers Endgame posters side-by-side

As The Avengers’ roster changed in the MCU and he began working alongside other superhero teams, Robert Downey Jr continued to form friendships with his new co-stars. Benedict Cumberbatch co-starred in Avengers: Infinity War alongside Robert Downey Jr, with Cumberbatch noting how much he enjoyed working alongside Downey Jr. Robert Downey Jr also became friends with Chris Pratt while working on Infinity War and defended Pratt when he was harassed on social media.

However, Robert Downey Jr’s most famous MCU friendship is with Tom Holland; with Downey Jr helping Holland get his career-defining role as the MCU’s Spider-Man while working on Captain America: Civil War. Just as Tony Stark helped found The Avengers and later took the role of mentor to Peter Parker, Robert Downey Jr similarly mentored Tom Holland. Holland has spoken of his positive experience working with Downey Jr during his audition and first scene as Peter Parker, noting that some of the dialogue was improvised, leading to the scene’s natural, jovial feel. Even after Robert Downey Jr’s MCU tenure ended in Endgame, he and Holland continue to show their friendship on social media and even co-starred in the non-MCU film Dolittle. As with the original members of The Avengers, Robert Downey Jr naturally falls into the role of both mentor and friend to his co-stars.

Next: Iron Man 3: Why Tony's "Perfect" Armor Looked So Weak