Honestly, I don't even truly know what I just watched. Did I, however, absolutely thoroughly and undeniably enjoy it? You betcha! That's probably thanks to the outstanding cast, rather than anything else.
Cillian Murphy is utterly superb in this, I loved his performance as Tom. It's no surprise given what else he has done, he's a great actor to watch. Murphy isn't alone in 'Red Lights' though, as he is joined by other notable performers. Sigourney Weaver (Margaret) and Robert De Niro (Simon) are also terrific, they add a lot with what they give. You also have Elizabeth Olsen (Holly) and Toby Jones (Paul) involved too. Top casting!
On the other hand, the premise - or at least how it's shown - isn't as great as it could've been. I still enjoyed it wholly, but that's probably because the film makes a lot of noise around the story and builds up the tension well. However, when you break it down after watching it isn't anything as outrageous as you might feel at the time - at least that's how I view it. Some more development into the characters would've been nice, for example.
Nevertheless, the film done its job and made me feel entertained and enthralled into what was happening. It's difficult to criticise it due to that, to be honest. I'll leave it to others to dive deeper into it, but all I can say is I practically loved it.