Marvel's Cinematic Universe has indeeed become very vast, especially since they crossed from films to television series. As it turned out, with "Avengers: Age of Ultron" coming to theaters in a couple of weeks, they still have a few surprises in store for the fans.

According to Screen Rant, the final stretch of the current season of "Marvel's Agents of SHIELD" is leading towards "Age of Ultron." While the series is wrapping up, Netflix is also getting ready to premiere "Daredevil" starring Charlie Cox (because Ben Affleck abandoned that role for the upcoming "Batman v Superman" film set to be released next year -- or not).

Other than that, there's another tease from Robert Downey Jr., saying that a "big announcement" is yet to come.

But while everyone is speculating on the big tease, Cinema Blend noted that there will be at least three characters from "Marvel's Agents of SHIELD"who will make their appearance in "Age of Ultron" -- May, Daisy, and Coulson being the first ones on the list.

In case those names don't mean anything to you, "May" refers to Agent Melinda May, the motherly figure whom the rest of the agents look up to in the series (because she's kick-ass like that), played by Ming-Na Wen.

"Daisy" is Daisy Johnson, Chloe Bennett's wise-cracking hacker, Skye, who also ended up being the superpowered character, Quake.

Finally, Coulson is Clark Gregg's character, Agent Phil Coulson, who appeared in most of the post-credit scenes in the "Avengers" films, and who also supposedly died in the first "Avengers" movie.

Of course, if they will appear in the film, Cinema Blend notes, they will probably have very minor roles, maybe verging on cameos. However, this will give the series the boost that it needs to stay afloat for the next season.

It is helpful to note that these three characters' appearances are still mere speculations at this point, and may not even be true. But if in case there is a semblance of truth in these rumors, then it will be something that fans can look forward to.

SHIELD members are still probable inclusions in the show, but there are three other characters that have already been confirmed. According to Inquirer Movies, Andy Serkis, Thomas Kretschmann, and Claudia Kim are going to appear as Ulysses Klane (a black market arms dealer), Baron Strucker (a HYDRA scientist working under SHIELD) and Dr. Helen Cho (a world-renowned geneticist and ally of The Avengers in South Korea) respectively.

How likely do you think "Agents of SHIELD" members will be appearing considering that there are already three more characters added in the cast list?