In Overstrike, you play as one of four agents of Overstrike 9 which is a team made up of an ex-mercenary, thief, scientist, and detective as they come together to stop a terrorist organization from wiping out all of humankind. Since Insomniac is known for making some lethal weapons and gadgets, as well as witty dialog and an interesting storyline in their games, you can expect Overstrike to receive the same kind of treatment.
One of the key features of the game will be its four player co-op. I'm curious to see how the players will interact with one another as it seems Insomniac Games has thought of a strong background story for each character, but has yet to disclose any further information regarding the game. For now, all I can offer you is the reveal trailer which I've embedded below and I'm sure you'll be entertained by, even though there isn't an ounce of actual gameplay footage.