*SPOILER ALERT*
I won't lie, I found the show fairly riveting up until the big reveal near the end concerning the nature of the Jonathan's liaison with with Catherine.
Of course early on I realized that the flashbacks we were being shown were not flashbacks but scenes from the book that Jonathan's mother had written, details about which she could have known next to nothing.
I had figured the truth was very different from the wet dream fantasy the book presented, but I admit I did not predict the show would go in such an extreme direction, turning Jonathan into a gibbering psychopathic rapist.
Frankly, I found it outlandish. There was simply nowhere close to enough foreshadowing or any kind of clue to suggest that Catherine had been the victim of a violent rape or that Jonathan was capable of such a crime. The scenes attempting to hint at this concerning the real reason the girlfriend left Italy delivered about 5 minutes before the big reveal felt like narrative backfilling; a half-baked attempt to justify the ludicrous whiplash plot device of turning Jonathan into a stone cold monster and Catherine into a victim of brutal violence.
But if there's one plot contrivance that simply gobsmacked me and robbed the story of its last shred of credibility it was the sudden 180 degree about-face delivered by Stephen. You're telling me that this guy - THIS GUY - the Machiavellian vengeful father who orchestrated the whole macabre revenge plot against Catherine, having heard Catherine's story relating the brutal rape at the hands of his son, just flat out swallowed her story whole, with zero evidence, and instantly changes his tune at the last second? Why? Is it because Cate Blanchett is a really good actress? Or maybe Galadriel bewitched him.
And then in a hallway of a hospital in the space of about 15 seconds he just blurts out to Robert that it was all a terrible mistake and she was really raped by his son (off camera) and the very next scene Robert has forgiven everything. Again, total narrative whiplash. This is Saturday morning cartoon level writing.
And Robert rightly asks her: why didn't you tell me? And while to be fair, I can't see him believing her easily given the photographs (and ya, sorry, the idea that those photos were taken in the course of a violent 3 hour rape at knifepoint by a coked up psychopath is not something I am prepared to accept) the idea that she didn't once mention it or blurt it out, or successfully inform him - that's just ridiculous.
Bottom line, I felt like the first 3/4 of the show were written by one set of writers and then maybe their final paychecks didn't clear and the story had to be finished over a weekend by a producer or something. Just a total letdown of a final act.