New, most probably spoilerish, information has been uncovered involving Iron Man 2.

So what follows after the jump is most likely considered a spoiler. Even though the image appears in the official trailer, which is playing on the big screen in front of Sherlock Holmes, the details are very hard to notice. In fact, the image above might even feature the spoiler in question, but unless you knew exactly what you were looking for, you wouldn’t be able to spot it. Basically, what I’m saying is, don’t read any further unless you care to learn a possible major plot point from the upcoming sequel, okay?

You ready?

You’ve been warned…

The first three production photos released by Marvel Entertainment…

…do not feature the potential plot detail in question, but the below image, screencaptured from the new trailer, does:

Do you notice that patch on Scarlett Johansson’s arm? That looks like the insignia for S.H.I.E.L.D… That’s right, Black Widow becomes an agent of S.H.I.E.L.D.! The patch was discovered by some comic book fans on a forum, sent to me via /film reader Craig M.

The news that Black Widow becomes a member of SHIELD is not a huge surprise as Johansson has hinted that she might return for the big screen team-up film The Avengers. Johansson once told Ireland-Online:

She has many different incarnations and different storylines so I’m hoping she will be able to continue in that way. I’m hoping that if the fans like the character and support the character, we’ll see her again…I hope I get to come back and do it again. The character certainly comes back. We see that she does in the comics and certainly she is a big part of The Avengers. I don’t know if that is where it’s going to go but she is definitely a big part of The Avengers.

And when asked who would make-up the Avengers team, producer Kevin Feige told io9 in July:

I think we know. I think it’s going to be Iron Man and Thor, Captain America and Nick Fury. I think it’s safe to assume that there will be some members of the Hulk universe in the film as well. In terms of the additional I think Black Widow, sure. The SHIELD organization for sure. What’s exciting, for me, about The Avengers movie is seeing those four characters interact with each other. I think anywhere from the first issues of The Avengers to Civil War the dynamic between Steve Rogers and Tony Stark is just awesome, it’s fascinating. It brings out sides in others that won’t be brought out in the other franchises. Going forward with the mix is a whole other thing, I think it will be cool. So to pile on another 15 or 10, frankly more than four would be too many.

Of course, in the comic books, Romanova attempts to seduce American defense contractor Tony Stark, inevitably confronting Iron Man, defecting to the United States to join the super-team the Avengers.