The five leads in this movie do what they can. They are likable actors and they have some moments of conviction here and there, but the script is so horrendous it's astonishing that they can keep a straight face delivering these lines. Wentworth Miller is the weak link, and I don't know if it's his fault or his character just being really weird and uncomfortable but that's another thing: you don't like any of these characters. They're all despicable, cheating, lying, douchebags that are only friends because they all have those sh*tty traits in common. And I use the term "friends" loosely because these guys seem to hate each other as much as the audience does. Half the time they're yelling and arguing at each other, the other half they're just dull and plodding along with the script. It's sad because you want to like these guys but they really are just sociopathic dickheads. Honestly the only one with a conscious is James Marsden's character but even then still he's a deceiving slimeball. However the cokehead brother completely embraces the psychosis angle and gives a very nice standout performance considering the material he was given.
The women in this movie are horrendous. There is not one memorable female character - they're all either stupid and married to these guys or stupid and f*cking them behind their wives' backs. It's hard to care about a movie where every character is totally unlikable.
Like I said, the first half of the movie is very promising. The pacing was appropriate, it was easy to follow what was going on, it gave you time to become invested in the mystery, then all of a sudden things get crazy. Like unbelievable, ridiculous, stupid levels of crazy. First of all there are like six endings to the movie; it goes on for a good 10-20 more minutes than it should, and the worst part is that each "ending" is worse than the last. They try over-explaining what happened and it ends up getting so twisted and convoluted that it collapses onto itself. At a point you just stop caring about who did what - you just want the damn movie to end. The entire third act is a disaster in every conceivable way.
This movie was watchable, mainly because of the cast, but the ending is so frustrating I had to give it a low score. I really tried to like it, it's just hard to care about a movie when you're just watching a bunch of stupid people do stupid things. And the police interrogation scenes were atrocious.
If you don't care about plot and just want to see a bunch of good looking people act like complete jerks for an hour and a half, you can get a kick out of The Loft. If you want a thrilling murder mystery that makes you think, stay far far away - The Loft does not deliver.