If you have ever wondered, how much action you can pack into one film, here is the answer. Crank is nothing but pure action, from start 'til end, no exceptions. It's got everything an action movie can have, from car chases, over fights and shootings to helicopters and machine guns.
And, apart from that, the camera work is pretty cool as well. It starts off with some camcorder optics, which come back often later on, which makes the whole movie even faster and more tense.
And it IS fast - by far one of the fastest films I have seen so far. And not the boring kind of fast you might know from stuff like "The Fast and the Furious", where the fast scenes are all alike, but a really surprisingly big amount of different scenes, all at the same high speed.
So if you like action - much action - and you like fast films - very fast films - then this movie will surely convince you.