It's no secret that Dune is a very long film. At 156 minutes long, the Denis Villeneuve movie only managed to adapt the first half of Frank Herbert's novel. However, there were still a lot of key moments from the book that didn't quite make it into the adaptation. Interestingly, there is a deleted scene featuring Lady Jessica that would have shed some light on one of the story's tragic figures.
In Dune, the House Atreides was taken down by the Harkonnens with the help of Doctor Wellington Yueh. Duke Leto Atreides' personal physician is revealed to be working for the Baron, who had captured Yueh's wife and is using her to blackmail the doctor.
The truth about Yueh's wife is only revealed right before the doctor's death. However, the character's story arc would have been confirmed in a deleted scene featuring Lady Jessica. In the scene, Leto's concubine talks to Yueh who opens up about his wife. At one point, the doctor sheds tears over his wife's situation.
The conversation with Lady Jessica would have been important in establishing the reason why Yueh later betrays Leto and his family. The deal he has with the Baron is that he would be reunited with his wife if he does the Harkonnen's bidding. Unfortunately, Yueh's wife (who is a Bene Gesserit too) had been killed long before the physician completed his mission.
But why was the scene deleted from Dune's theatrical cut when it could explain Yueh's motivations? There is too much going on in the story and the film would need to focus on the main storyline. Still, it could have been great to give Yueh a moment in the spotlight.
Yueh is played by Chang Chen while Lady Jessica is portrayed by Rebecca Ferguson. Dune is still screening in theaters nationwide.