Some things I don't get (yes, I know it is tev but still!).
If you have not watched yet, please don't read any further as it gives away the ending.
So, the business partner hit greg on the head but:
A) would the post mortem not have shown that he'd been bashed on the head?
B) how did the crash happen then? I am assuming that the business partner put them both in the car and put the car off the road and set it on fire but surely there would have been skid marks on the road for the police to investigate.
C) would Ellie really have suffered such injuries to her face and legs from that crash? Would he really have died? She can't have been driving that fast.
D) Surely the police would not, ever have let her away with it by accepting she just couldn't remember?