The Large Hadron Collider people failed to destroy Earth with a black hole. Not all good though, they introduced a rather Hellboy problem. Opened a rift to Hell. Stuff tends to come through those and kill people.
An officer survives the attack and gets drummed out of the army for telling the truth about what he saw. Good old coverup.
Privately funded organisation hires him to put together a team of bored ex-Special Forces types from multiple countries keen enough to take a crack at killing monsters, people being too boring.
Or A Scotsman, a German, a Russian and an American walked into a Hellmouth...
3.5 out of 5