I have to be honest, I was looking forward to this film so much, but I left the screening disappointed.
The acting is okay, but Reilly is miscast. There is one particular scene near the beginning between Reilly and Dafoe that was just so cringeworthy, Reilly was totally out of his depth. I haven't read the book but I assumed the scene was meant to be taken in a serious tone, but it just came off in a comical way.
The effects were also pretty poor and it in a way reminded me of Twilight. I'm guessing that, like Twilight, the budget wasn't really there and they were hoping that the movie would be a big enough hit in order to warrant a much bigger budget for the sequel. The Twilight franchise got their wish, I doubt the Cirque Du Freak franchise will.
All this being said I thought the story was decent, and I was entertained and happy enough until the last 20 mins or so where the film fell flat for its' finale. It's definitely a decent film, a think the rating of 10% among top critics on Rotten Tomatoes is very harsh. I would say this reaction has been born out of frustration with the genre more than anything else. I say this because some of the criticisms make no sense. One critic says it's hard to know where you're at watching the film, I thought it was pretty straight forward and never felt confused. Another critic said that Chris Massoglia made Daniel Radcliffe look like a talented thesp, again I think this is very harsh, especially given that Radcliffe has a lot more to work with than Massoglia and is still pretty poor.
2.5/5 for me, it would have been 3 if the finale was stronger.