How long did Matthew Macfadyen know about Succession's Season 3 finale twist?

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"We had a conversation early on before we started shooting, which outlined a possible scenario for the end," he says. "It’s a funny one, I listened to it, then forgot about it, because things might change, and whatever they want to do is great. I wasn’t hanging my hat on it, and I was just waiting for the script to come in." In a separate interview with GQ, Macfadyen adds: "I can honestly say, hand on heart, that there hasn’t been a scene since we started doing this show that I haven’t really enjoyed and relished and adored. It’s such fun. And it’s not just fun, it’s interesting and weird and odd, like people are. That’s the real skill of the writing and the story. It’s not black and white, it’s odd. They’re repellent and sympathetic at the same time. We don’t know what we feel and what we want, and it’s ok for the characters not to either. It helps when you work with a wonderful cast and crew, the crew are the same since when we started. So there’s a lovely continuity, it feels like a big company."