Terrible acting, screenplay and direction.

Fun premise, good actors, bad writing. This film seemed to have potential at the beginning but it quickly devolves into a trite action film. Ultimately it's very boring.

The movie's neither hopeful in contrived ways, nor hopeless in different contrived ways. Somehow it manages to be wonderful

Yes, absolutely, there is fun to be had, as well as many, many things to go boom, all amid an atmospheric urban jungle.