The original Underworld could best be described as a movie made according to the rules of the World of Darkness roleplaying universe from White Wolf, postulating a supernatural underside to our familiar world where vampires and werewolves battle endlessly, with a plot based on cliches filtered through the rules of Hollywood scriptwriting. Despite that, it actually worked pretty well. The key, as with many such movies, is to ignore the plot holes, physics errors, and lack of characterization, instead focusing on shiny things that go bang, fanged cool factor, and Kate Beckinsale in a shiny skintight corset-enabled piece of tactical eveningwear.
The sequel, Evolution, has all the advantages of its predecessor, and fewer disadvantages. The script is better, though still definitely an action movie script; the action scenes lack the awkward moments that occasionally showed up in the first. The romantic interest of the two main characters is inevitable, but having been established in the first movie now takes up much less exposition time – which is instead spent on mild plot twists. The special effects are similar in feel, but improved significantly. Fight choreography is smoother, and more realistic, although not always cinematic due to realistic fighting being less flashy. Bonus points for ammunition management; characters actually reloaded multiple times and ran out of ammunition eventually.
Definitely no deep meaning to this one, but I enjoyed it.