Splice is about two brilliant genetic splicers, Clive (Adrian Brody) and Else (Sarah Polley), who have been working on a genetic breakthrough: the creation of new creatures that can produce a protein valuable to human medicine. However, when they learn that their splicing facility is being shut down, they decide to break the rules and add human DNA to the splicing, creating a creature that is part human. The pair plan to kill it, but when Else starts developing maternal feelings for it, it becomes a responsibility that is dangerous in more ways than they ever imagined.
The film gets off to a terrific start, with a great premise and solid chemistry between Brody and Polley; they're a rare screen horror pairing (or, honestly, screen pairing in general) that you can believe would be attracted to one another. They're both shamelessly geeky, proud nerds who flaunt their intelligence as their defining characteristic. The creatures they create legally, Fred and Ginger, and the illicit Dren are deliciously grotesque creations, legitimately creepy and unsettling. Director Vincenzo Natali (who co-wrote the script with Antoinette Terry Bryant and Doug Taylor) is like a commercialized hybrid of David Lynch and David Cronenberg, lending the proceedings disgusting gore and a skillful blend of themes as he taps into the ethics of genetic splicing, the fear of what lurks with us, and, most impressively, the horror that is raising a child. Splice succeeds best on this front, as Dren becomes a surrogate child for Clive and Else, and they face the same kinds of problems that the parents of "normal" children face. Its a clever move for the film to take, and one that I wish the film would have explored further.
Unfortunately, the whole thing falls apart in the third act. As Dren grows up, she becomes more and more volatile, since she's now entering her teen and adult year. This leads to some interesting ideas; but the film decides that the best of them is for Clive to have sex with the creature. From here, what could have been delightfully weird just becomes stupid, with a lame final act and a revelation that's a groaner (even though it shouldn't have been). The film just completely throws everything it had been building towards out for a mediocre "horror" finale that ditches the logic and character development it had been building in the rest of the film. It could, and should, have been transcendent. Instead it just falls on its face.
Splice is two-thirds of a great cerebral horror film, one that could have ranked among the ranks of the best. Instead, it ends up squandering that promise to be one of the most disappointing films of the year.