Sure. You'd be classified as hero by the rest, and not largely trusted by the human population, but through acts and other such ways, I'm sure you could get them to come around.
- - - Updated - - -
So basically, If you wish, You can play a hero.
Also, Probably should have mentioned this in the OP, There can me minion players. Basically those are stronger than your average soldier for the overlords, but weaker than overlords think.....Wolverine to the Silver surfer.