Body Of Proof - Dead Man Walking

This is another excellent episode of Body of Proof!  This show is so well written.  I can't believe the number of red herrings one show can cram in to one hour of television!  How the hell anyone can pick the killer is beyond me, which is great.  It kept me guessing through the whole episode.
So this story commences with a man, obviously very sick, being followed by an African-American man in what looks like a suspicious way.  The sick man calls out for help. He is later found dead.  After some investigation, Dr Hunt finds that the man had just had surgery and he was not clipped up correctly and he bled to death internally.  Was this intentional or just a terrible accident, a case of malpractice?
First off they make it look like the African-American killed him, then when they figure out it was to do with the surgery, it comes back to: was it the surgeon who is lax in his job?  Was it his nurse who points the finger at the surgeon?  Is it the surgeon's boss?  Or is it the victim's wife who is linked to the place where the African-American works?  So was it him after all or was the wife meeting someone else at the same place?
This really is just brilliant!
The 'B' story this week has Ethan falling for the twin sister of a woman (played by Firefly's Christina Hendricks who interestingly has also supplied the voice for the animated Lois Lane along with Dana Delany!) who dies suddenly of a blood clot while staying in a hotel room.  At first they believe she got DVT, but the twin advises that her sister hadn't been on a plane.  Ethan discovers it's hereditary and that the twin could also die from the same thing.  Can he save her AND go out with her at the same time?
A very cleverly written episode again.  If you are not watching Body Of Proof, you need to start watching now!