Underworld: Evolution
The good idea:
Kate Beckinsale in a leather jumpsuit, lots of non-stop, over-the-top violence with a gothic vision.
What worked:
The film tries to infuse a larger story into all the action: Enmity and hatred spanning centuries coming to an end (Marcus freeing William); father-son guilt and loyalty (Corvinus's inability to kill his sons has cost many lives over the centuries); and psychological ghosts and demons from the past informing the present (Selene discovers her own father's actions were not arbitrary).
What didn't work:
Unfortunately all of the above comes across in long expositional speeches by Derek Jacobi midway through the movie and through various flashbacks and blood visions. While the opening flashback sets up the outer goal of Marcus wanting to free his brother William, it doesn't clearly convey why. Is it world domination? Revenge? What is their unfinished business?
Also, Selene, played by Kate Beckinsale, is compelled to stop them for no apparent reason other than if she doesn't there wouldn't be a movie. Again, without knowing what the stakes are if the brothers reunite, her reasons for stopping them seem arbitrary. Marcus is coming after her because she literally has the key to finding William but why does she feel compelled to stop his dastardly plan, if he has one?
A couple of missed opportunities story-wise. Michael, a hybrid, has special powers. However, those special powers never seem to come into play. He's just as strong and has many of the same abilities of his enemies (jumping long distances, absorbing bullets, jaw ripping strength). The reason for his Act III resurrection is muddled. Did he arise from the dead because of his special powers (though still undefined) or from Selene spilling her blood into his wounds?
Selene is a vampire and thus, cannot be exposed to sunlight. This is established at the beginning of her story when her hands and face burn at sunrise. When she drinks Derek Jacobi's blood he tells her she will have greater powers than before. However, it doesn't appear that these special powers ever come into play. She uses only her well established abilities in the climatic fight. After the climatic fight is over, the sun rises and Selene is able to stand in sunlight without danger. Perhaps a more integral use of this newfound ability would have been to have the sun rise during the climatic fight and Marcus becomes over confident that he has won because she will now die in sunlight. Her ability to survive sunlight allows her to defeat Marcus. This way, drinking Derek Jacobi's blood affects the outcome rather than reading as a nice bonus at the end.
Despite its storytelling ambitions, the only thing you really need to know to follow the plot is that the attractive people are the good guys (as good as good can be in this world) and the ugly people are evil.