I Don't Feel at Home in This World Anymore

I get that dark humours can work amazingly well (Harold and Maude,Fargo, American psycho, Four Lions) but it can also flop completely (Let's kill Wards wife, Serial Mom, Blank) and this film blurs the line of these two qualities. It started off great with the perfect blend of comedy and thriller then at the end it faded into pure thriller and the gore was suddenly turned to a strange degree in comparison with the rest of the film. This can work but it simply didn't in this one. Well acted but an out of place finish