Anthony and Joe Russo filmed the two blockbusters back-to-back, and will be putting the finishing touches to Avengers 4 between now and its release early next year.
After Infinity War left fans stunned and broke multiple records at the box office, it seems the best is still yet to come.
Joe told Deadline: “You know, we’re very proud of [Avengers 4].
“I think ultimately Avengers 4 may be our best work for Marvel. I think we’ve grown with every movie that we’ve made there.
“We’ve grown with the characters. We’ve grown with the cast. As filmmakers we’re very happy and very excited with the movie.
“I feel like with Avengers 4, because it was made before there was any response to Avengers 3, it’s really pure in that regard. The storytelling is very pure.
“It’s without any sort of external noise creeping in at.”
The events of the next film remain a mystery, but Infinity War ended with 50% of all humanity being killed – so we’ll certainly be joining our heroes in something of a dramatic state.
Even the title of the film remains a mystery, with Marvel boss Kevin Feige saying recently: “That’ll be after the Captain Marvel teaser probably, announcing that title.
“It’ll be towards the end of the year with however we launch that film.”
He has also promised that Avengers 4 will bring a definitive end to the current phase of Marvel films.
“We’re one decade in. In the comics, some of these heroes are five, six, seven decades in. So I do hope they continue for a long time,” he told Toronto Sun.
“But, storylines can come to an end. The best stories do come to an end. Return of the Jedi was an ending for a long time and as a 10-year-old in 1983 that carried me through 30 years until there was a sequel.”
Avengers 4 is out in April 2019.