Marvel is building up the hype for Avengers: Infinity War, as the blockbuster movie's first trailer was shown at D23 panel on 15 July and yet again at San Diego Comic-Con panel over the weekend, but the company is yet to officially release it worldwide.

However, following its SDCC panel, a pirated version of Infinity War footage was leaked online, which was later taken down by the production company. Director Joe Russo has given an update on when Marvel fans can expect the first trailer.

Speaking with ComicBook, he said, "You know, all I can say is that when the footage comes out we want it to be exactly right. So we are taking our time and working on that footage because, as you can imagine, the levels of visual effects in these movies are unprecedented and there are certain things in this footage at Comic-Con that works specifically for a Comic-Con audience."

"But when we go wide, to a wide audience, we have to make sure that footage works for a wide audience," he added, explaining why the Comic-Con trailer is not released officially. From his statement, it looks like the trailer will not come out anytime soon.

The upcoming movie has often been called the culmination of everything in the Marvel Cinematic Universe since Iron Man movie came out in 2008. This means fans can expect the death of some of their favorites superheroes.

Joe Russo has asked the fans to be prepared for an "end". He was quoted as saying, "My brother and I believe in stakes. I believe that everything has to have an end at some point in order for it to have value. The audience should be prepared."

Marvel president Kevin Feige also teased "death" presence and said, "Death has been a presence in the MCU up until now." Further confirming fatalities in the hands of Thanos, the main villain of the movie, Feige added, "Thanos - death follows him like a shadow."

The movie's star cast includes Robert Downey, Jr., Chris Evans, Chris Hemsworth, Mark Ruffalo, Jeremy Renner, Scarlett Johansson, Tom Holland, Elizabeth Olsen, Paul Bethany, Sebastian Stan, Benedict Cumberbatch, Benedict Wong, Chris Pratt, Zoe Saldana, Karen Gillan, Vin Diesel, Dave Bautista, Bradley Cooper, Pom Klementieff, and Josh Brolin as the villain Thanos.

The film hits the theaters on 4 May 2018.