HaBO: It was a Film, and Maybe a Book

You did it! We figured this one out! It is a truth universally acknowledged (by me for certain) that the Bitchery pretty much knows everything, and really, it's true. Scroll down to see the solution for this HaBO - and many thanks!

Jan asks for your help with a film she saw and is pretty sure was once a book, too:

This one has been bugging me for ages, but I’m not sure it’s an actual
book. It’s something I saw on tv – but since it’s an historical I’m
pretty sure it was a book too. I surely hope it is.

I saw this movie some 10 years ago, probably more. I was a very young teen.
I’m not sure what period it was in, because I was so young all historicals
were still the same period for me. If my memories serve me right, the
costumes looked more like the ones from Clarissa (with the yummy Sean Bean
as Lovelace) than the ones from a Jane Austen movie. I was old enough to
read subtitles though, so it’s not longer ago than 15 years.

If I remember right the story was mainly told from the perspective of the
hero, or if it was the heroïne, the hero got a lot of attention when they
weren’t together.

I believe either or both of them were scientists or interested in science (I
think plants and animals and stuff like that) and they had lots of
intelligent conversation about that. However the hero falls (is tricked?)
for a prettier (and richer?) woman. They marry, and she gets pregnant soon.
Years pass and his wife turns out to be very cold, only letting him in her
bedchambers once a year. She gets pregnant every time. After years of being
married unhappily he finds out that the reason why all his children look
like his wife is because they are not his, but from her brother (eww).
He leaves then (I think to live with the heroïne – but I don’t recall the
end).

There’s also a scene where the brother rapes a maid, and the hero
interrupts (and saves her).

The evil family were blondes (and thus all the children too), but the hero
and heroine were darker in complexion.

I’ve been hoping it would be on tv ever since I remembered this story, but
it hasn’t. If this is some sorts of classic of English Literature I’ll
probably feel stupid, but I’m from Belgium, so my knowledge of the classics
is incomplete.

I really hope somebody knows what this is, if it was only a movie or also a
book, because I want to find out if he went to live with the heroine or not.

Jan tells me the film was in English with Dutch subtitles when she saw it, and she’s not 100% sure it’s a book. Sounds to me like the Hell Version of Flowers in the Attic. Anyone remember this… majestic plotline?