I called Avengers: Infinity War the Nashville of Marvel Movies (due to the oversize cast), it's companion film Avengers: Endgame is first and foremost a Marvel Movie, the triumphant culmination of the series after 22 films. Endgame has the feel and even some of the structure of Return of the Jedi, and even took a serious amount of inspiration from Back to the Future II (and nearly every other time travel movie). Engaging from start to finish and filled with bright humor, but also emotional and melancholy at times. Audiences have spent over a decade with these characters, and that strong emotional connection is more than enough to warrant the three hour running time.
The film is divided into three acts - all well executed. The story picks up with the aftermath of Infinity War in the days after Thanos wiped out half of humanity. The remaining Avengers are left to pick up the pieces. The first act is about the struggle to find hope amidst debilitating defeat. The middle section involves a complex quest that involves time travel, a "time heist" to quote Paul Rudd's Ant Man. The last section is the inevitable confrontation with Thanos (Josh Brolin) - followed by an extended epilogue.
Without going too much into plot details, time travel adds some wonderful complications to the plot. These sequences lead to some humorous and surreal moments. Old rivalries and grievances are put to rest as the Avengers agree to reunite to for one last chance to make things right. Endgame reminds of the WWII movies when a small group of rag tag fighters must somehow find a way to overcome the odds (The Dirty Dozen, Guns of Navarone, The Great Escape).
A word about the actors. Robert Downey is the lead in Endgame, and continues to evolve Tony Stark. Scarlet Johansson as Black Widow been under served in the Marvel films, but is given more of an arc in this time. Chris Evans as Captain America gives a soulful performance, especially effective in a scene when he's consoling those in grief. Mark Ruffalo and Chris Hemsworth supply much needed comic relief. Those examples only scratches the surface, the entire cast were all given memorable moments.
As a movie Endgame also takes much from epic movies of the past. There's the grandiosity of Cecil B. Demille and grounded story telling of David Lean. The direction by the Russo Brothers did a fantastic job tying all the story lines together. The dialogue owes much to Quentin Tarantino and screwball comedies, as well as the comic lingo of Stan Lee. Everything in the film recalls classic Marvel comics - character conflicts, action sequences, and sly humor. The use of CGI is everywhere, by this point these movies have achieved such a distinct style and look that's been honed and improved over 20+ movies, so I can overlook the CGI heavy sequences.
Fans of these movies will cherish Endgame and maybe even win over some of the skeptics. A towering film in every way. For a time I was dubious of the Marvel films, but the series did get progressively better. Endgame is a perfect conclusion to the series.