In crafting Infinity War, the Russo brothers faced a much tougher task behind the camera than their Avengers predecessor Joss Whedon. The first two superhero team-ups were relatively Earthbound stories that didn't veer too far into the cosmic side of things, but the third installment's narrative spans the length and breadth of the Marvel Cinematic Universe and as a result constantly finds itself in a tonal juggling act. Thankfully, for the most part the movie pulls it off.
Incorporating the mystical elements of Doctor Strange, the intergalactic buddy movie dynamic of Thor: Ragnarok, the wacky space comedy of the Guardians of the Galaxy and more into a story already bursting at the seams seemed like an almost-impossible task, but fans are now so comfortable with the Marvel formula that these tonal shifts never come across as overly-jarring, and even provide some of the movie's funniest moments.
Seeing Groot interact with Captain America in Wakanda seconds after watching the high school-aged Spider-Man team up with Drax to battle Thanos in space is an interesting sentence to read, and one that would have seemed impossible a few years ago. It is to Infinity War's immense credit that it manages to balance so many disparate tones and genres into a generally-satisfying whole, especially with how massively the mythology of the MCU has expanded in the three years since Age of Ultron.