It's a serial killer movie with Keanu Reeves as the bad guy. This is not promising.
The weird thing is that apart from that, the film's okay. It's nothing special, but I like James Spader's character and it's a perfectly good police procedural. Keanu's character has some weird things going on in his head and I basically quite enjoyed it. However... Keanu. This is going to take a while.
Firstly, I don't mind Keanu as an actor. He can be used effectively, e.g. The Matrix, or Bill and Ted. He's also good in The Gift, which was released the same year and casts him as a wife-beating redneck. What all these films have in common is that they're not requiring him to project intelligence or thought processes. There's something Zen about Keanu in the Matrix trilogy, as if he's the living embodiment of the instruction to "clear your mind". Within these parameters, he's quite good at looking cool.
Here though, he's a serial killer. If you ever wanted to see a movie character's thought processes, this would be it. The whole point of the story is his cat-and-mouse game with the hero. Now in fairness Keanu's not a complete dead loss since you can go a long way with zen inscrutability and coolness, e.g. the scene where he kills cops. However the entire third act is based around Keanu's obsession with Spader and culminates in a talky confrontation scene, with which Anthony Hopkins would have been killing half the audience with heart attacks, whereas Keanu's just sort of there. He's not scary. You're not worried about what he might do. You're not even particularly interested in what he might have to say. He's just Keanu. Now even this problem isn't enough to kill the movie, since despite him it's still a good and really twisted scene, but it does mean that the movie deflates a bit towards the end.
Still more puzzlingly, Keanu wasn't even cast for his star value, since he's third-billed after James Spader and Marisa Tomei. In fact he'd promised several years earlier to be in the movie, with his role having been planned as a cameo. In the meantime he became a massive star and the production team were able to use his name to get a bigger cast and budget than they'd planned, of course rewriting his role to make it bigger. Keanu wasn't happy. It was still only a supporting role and he'd only be paid scale. He tried to drop out of the movie, but eventually changed his mind on condition that they downplay his involvement.
I still quite enjoyed the movie, though. I can see the obvious problems, but I'd been bracing myself for Keanu and in the end he works better in the role than I'd expected. He's convincing, which was a surprise.
James Spader I liked a lot, though. He'd been hunting Keanu so long that he's now retired, hopped to the eyeballs on drugs and seeing a psychiatrist twice weekly. The guy's a wreck. However he's also clever and shows it with a quiet simplicity that makes his inferences look trivial even when they're not, e.g. the coffee cups. I liked him. I like the way he makes his thinking so clear and natural. He's a good protagonist and I was happy watching him hunt Keanu for 97 minutes.
Then there's the psychology of Keanu's character. He thinks he's got a relationship with Spader. He even gets jealous. The gay subtext in this film is deafening, although I shouldn't think anyone would want to self-identify with Keanu's character, be they gay or straight. This film contains some really weird psychology and anyone claiming that this is just another cliched super-genius serial killer hasn't been watching properly. Keanu taunts Spader, yes, but it's far from just the usual cat-and-mouse.
Overall I quite enjoyed this movie, but this probably says a lot about me and I still wouldn't recommend it. It has odd problems. The incidental music does some farting tubas at around the hour mark, which makes a supposedly tense scene sound comedic. It all ends in a cheap CGI explosion. I drifted away during the chase scene two-thirds of the way through and the entire last act has that Keanu problem. Nevertheless the guy isn't the catastrophe in the role that you might expect, despite his Razzie nomination as Worst Supporting Actor, and the whole thing manages to be a halfway decent serial killer flick with a bit more personality than usual, thanks to the psychological angle. It's okay. You could watch far worse.