With the Marvel Cinematic Universe set to conclude its third phase, fans are already expecting many things to be included in the plans for Phase 4.

The Russo brothers Joe and Anthony, who will take charge of the developing the third and fourth movies in the Avengers franchise, has offered some information on what role The Avengers Infinity War and the yet untitled second movie will play for the future of the MCU, reported IGN.

"I can't get into too much detail about who we're introducing, but these two movies are intended to be the culmination of everything that has happened in the MCU since the very first Iron Man movie. In being a culmination, these movies are in some ways going to be an end to certain things, and in some ways, they're going to be the beginning of certain things," Anthony Russo said.

While the brothers refused to offer up more details on which things will end and which will begin, they assured that the decisions that they will be making for both movies will take into consideration what will be best for the overall plot of the movies as well as the future of the franchise.

The Avengers Infinity War was originally set to be released in two parts before Marvel decided to conclude the Infinity Stones story in one part and use the second movie to tackle another storyline.

In an interview with SlashFilm, the screenwriting tandem of Christopher Markus and Stephen McFeely shares the challenges of simultaneously working on both scripts and having to incorporate inputs from production, all while keeping track of the growing number of characters in the MCU.

"We're many drafts in. We're on the third draft of movie one and the second draft of movie two. [We're writing them in tandem] as much as we can. On any given day, you're only working on one but that doesn't mean that next week, you aren't working on the other one. And certainly, notes are coming in and all sorts of production stuff is coming in, like for instance, 'that thing over there is now a window not a door so adjust that.' Or, 'we're not going to this town now, we're going to this town.' That kind of stuff happens constantly and will continue to happen for the next few months," the duo said.