If you've seen the 'Captain America 2' trailer (or the 4-minute preview that ran in theaters with 'Thor: The Dark World'), you've already caught a glimpse of Crossbones, the Marvel villain played in the film by Frank Grillo. He starts off as an ally, but as you can see in the elevator beatdown, he eventually turns on Cap. Now, it looks like this isn't the last we'll see of Crossbones, as Grillo hints that Marvel has even bigger plans in store for the mercenary.

Grillo was asked by Crave Online whether Marvel has plans to use Crossbones in future projects and he responded:

They do actually. We’ll see what happens. We’ll see if the fans respond to Brock and how it goes...It’s fun. I can’t say very much about it because Marvel’s very strict about what you’re allowed to say.

If Marvel wanted to bring back Crossbones, they could certainly use the "Death of Captain America" storyline, which has Crossbones killing Cap. It would be an interesting way to end the 'Captain America' trilogy, allowing a new character to take over the mantle of Captain America in future films (in the comics, Bucky Barnes became the new Cap in Steve Rogers' absence). The problem with this is that a 'Captain America 3' would have to take place before 'Avengers 3' and we can't imagine Marvel writing Chris Evans out of their final film in Phase 3 of the Marvel Cinematic Universe.

Now, does this necessarily mean Crossbones will be returning for 'Captain America 3'? Not necessarily. In 'Captain America 2,' Crossbones is presented as a S.H.I.E.L.D. operative, meaning he could appear on ABC's 'Agents of S.H.I.E.L.D.' Alternatively, there could be plans for the character to appear in an upcoming Marvel short film (lately when characters say they're returning, this is how they return).

What do you think? Is Crossbones a formidable enough villain to lead an entire film? If not, who do you think should be the 'Captain America 3' villain?