A scene from “Unfinished Business”

Louis Mountbatten: Dear boy! My office rang Buckingham Palace what must be an hour ago, and I've been put through to about nine different extensions. Where have we finally reached you?

Prince Charles: Northeast Iceland, in a lodge on the River Hofsá.

Louis Mountbatten: What are you doing there?

Prince Charles: Salmon fishing with friends. You at Classiebawn with the gang?

Louis Mountbatten: The whole tribe, and everyone's asking after you. Are you gonna be in London next week? I'd like to see you.

Prince Charles: I won't. I have a rendezvous with Camilla. We've found a couple of days where we could catch up.

Louis Mountbatten: Oh, Charles, you're not still seeing her? You know what the family thinks.

Prince Charles: Yes, I'm perfectly aware of what the family thinks.

Louis Mountbatten: And what I think too?

Prince Charles: Yes, and the richness of that is not lost on me either. The idea that you, of all people, should lecture me about the sanctity of marriage...

Louis Mountbatten: [talking over Charles] I don't lecture you.

Prince Charles: ...and affairs of the heart needing to be conventional, because you and Edwina hardly blazed a trail in that department. At least when Camilla and I commit adultery, there aren't national security implications involved.

Louis Mountbatten: That was uncalled for.

Prince Charles: So is your unwelcome intervention in this matter. Honestly, you make a great show of being my ally in this family, watching my back, but when the chips are down, you're just a quisling. A fifth columnist playing for the other side. The fact is, I haven't met anyone I like as much as Camilla, who is herself trapped in a marriage of your engineering...

Louis Mountbatten: [talking over Charles] My own engineering?

Prince Charles: ...with a husband who's bedding half of Gloucestershire. Invite us both to Broadlands soon and you'll see how happy we actually make one another. That is, if my happiness is even remotely important to you.