Generally speaking you tend to find more murder mystery TV shows than movies, this is partially since it's hard to build a complete mystery in the allotted movie running time.
This movie builds this murder beautifully by showing the different points of views of the suspects. It has a different take than other movies since it gives the viewer a little too much details mid-movie which leaves you questioning everything to the last minute.
The acting was brilliant and I didn't feel the number of characters was overdoing it at any stage.