New updates and spoilers for "Avengers 4" reveal details for the launch date of its first trailer. Critics Choice reporter, Erick Weber, stated that Marvel Studios will launch the trailer before the year ends. Comic Book fans have been yearning for a trailer release since the aftermath of "Avengers: Infinity War" as the fourth film signals the end of an era and a new beginning for the Marvel Cinematic Universe.

"The Chronicles of Narnia" star, Tilda Swinton, will reprise her role as the Ancient One in the sequel. The fourth film is said to take place five years after the previous film.

The remaining MCU heroes must make a last stand against Thanos and save their fallen friends.

New 'Avengers 4' trailer details

According to Screen Rant, Erick Weber interviewed Marvel Studios head, Kevin Feige, regarding the status of the first "Avengers 4" trailer during a special reception and screening of "Black Panther." Feige did not reveal any specific details about the trailer, but he assured Weber that Marvel fans will see it before 2018 ends.

Weber also tweeted two other major announcements for the MCU. First, is that Namor the Submariner will be added to the cinematic universe. The second announcement is that "Guardians of the Galaxy Vol. 3" will be put on hold after Disney fired director James Gunn over controversial tweets.

It was previously reported that the plot of the film will involve time travel as Tony Stark will use the Quantum Realm to open a time gate with the help of Scott Lang.

Tony and Scott will travel to the events of the first "Avengers" movie on the eve of the Chitauri's invasion of New York, and rewrite history leading to the infamous "Thanos Snap" that wiped out haft of humanity in the universe.

Thanos eventually figures out Tony's plan and stops him from executing it, but he must face the full wrath of Earth's Mightiest Heroes as they will avenge their fallen friends and everyone else to save the universe.

The Ancient One returns

According to Comic Book Movies, executive producer Mike Grillo confirmed that Tilda Swinton will return as the Ancient One in "Avengers 4." Swinton's character first appeared in the "Doctor Strange" as a powerful and mysterious sorceress who protects the world from interdimensional threats.

The Ancient One is also the mentor of Doctor Stephen Strange, Karl Mordo, and the film's main antagonist, Kaecillus. Although good and noble, she hides a dark secret which Strange figured out. She is harnessing energy from the Dark Dimension where her mortal enemy, Dormmamu, resides. She dies in the movie, not before entrusting Strange with protecting the Sanctums and the whole world from Kaecillus and Dormmamu.

"Avengers 4" will premiere in cinemas on May 3, 2019.