In Inside Man we get the story of the vicar Harry Wotling, but the title character is Jefferson Grieff. Though we know that Grieff killed his wife, we don't know how and why, why she was tortured and mutilated afterwards, why her head was severed, and where it is now. My theory won't be able to solve all of this but I would like to reframe it, and summarise what we do know. All of the crimes that Jefferson solves from his prison cell, the audience is given all the facts about, and the answer is usually in the form of a riddle.

1. Why was the rapist paid for having sex with his wife? the rapist = therapist = clerical errors and misunderstandings

2. How does a man disappear in broad daylight wearing a tuxedo? He doesn't, he just blends in with the orchestra, goes home on his normal train and then gets murdered by his wife.

3. Where is Janice? No missing person's report was filed so she is at her last known location.

So what do we know about Mrs. Grieff?

1. Jefferson's main thesis in the show is similar to a line that is classic Joker about how anyone can be murderers given enough bad circumstances. He says in the award episode that most marriages are happy and loving. However he also says never come home early.

2. The father in law appears to be a notorious criminal. This is evident not only in his conversation with Jefferson, but in his conversation with the warden afterwards, when the warden says that the FBI are going to finally catch him. Could he have even been using his own daughter in his criminal enterprises?

So this is where my theory comes in:

Once upon a time there was a happy couple. The husband was a renowned criminology professor, the wife was young, beautiful, and always had a lot of money. The husband was even close friends with his wife's family, would drink with her father, talk psychology to him about the criminal mind. Little did he know that he was staring at a notorious criminal, sleeping with his daughter. One day Jefferson arrives home early, maybe taking the start of a well earned sabbatical. He hears erotic familiar noises coming from their bedroom. It is his wife having sex with another man, but wait, the tale gets worse and more sordid, the father in law his new best mate was filming it as pornography for the public. The story was going to be about a loyal wife who couldn't afford a few bills so she turned to paying them a different way, same old cliche but give the audience what they want. Jefferson is furious, chases the film crew out of his home, then enraged at this betrayal and about his wife's lack of reaction to being treated like this by her father proceeds to kill her. He decapitates her symbolically because he wanted to place her head in the father-in-law's bed like Godfather as revenge, but then decided that as a criminology professor that he should just do his best to bury it somewhere else in case he needed leverage later.

not much of a theory I know, but I look forward to your thoughts.