Dune is a classic science fiction novel by Frank Herbert. There have been attempts to film it, including an upcoming movie version covering the first half of the book. A lot of the names and vocabulary are clearly meant to evoke the Greco-Roman world.
Paul Atreides is the protagonist. Atreides is used as a family name and the name of a royal house.
Paul's father is Duke Leto Atreides. Leto is pronounced with an ɛ in the trailer.
Paul's mother, Lady Jessica Atreides, is a member of an order called the Bene Gesserit, with "G" as in "German."
I first read the book when I was a kid, so I had no idea if the words made any sense, and I guessed pronunciations, like Leto to rhyme with Cheeto and a hard G for Gesserit.
Is it actually possible to make sense of the words, and their pronunciation in the trailer?
Leto, I've now learned, is a goddess, which seems pretty off as the name of a patriarch -- assuming there isn't some other classical Leto who is male. I guess the name is Λητώ, so the accent is on the wrong syllable. I suppose it's debatable whether the vowel is right, since historically η was pronounced lots of different ways. One of them was probably the IPA vowel ε, as in the trailer.
Atreides is a genitive, used as a patronymic. So as far as I can tell it makes very little sense to treat it as a family name, or to have a Lady Jessica Atreides.
I don't know any Latin, but looking at a pronunciation guide, it seems like the soft G used in Gesserit in the trailer makes sense because it's followed by an "e." I suppose Bene just means good. Does Gesserit mean anything?
If it's thought more appropriate, this question could be moved to scifi.SE. There do seem to be some people there with knowledge of classical languages, e.g.: https://scifi.stackexchange.com/questions/197596/meaning-of-p-r-s-aes-triplex-in-heinleins-space-cadet