Olympus has Fallen took everyone by surprise, not just by being a fun blockbuster, but by making a fortune at the box office. It brought Gerard Butler back to what made him a star in the first place; balls to the wall, simple but effective action cinema. 

Now a sequel, London has Fallen has just dropped its first trailer - ahead of a release in 2016.

Newbie to American cinema, Babak Najafi, replaces Antoine Fuqua in the director's chair, while Butler and Aaron Eckhart return as the President of America and his trusty bodyguard.

If they keep the tone light, this could be a lot of fun.