As Endeavour's ninth and final season airs on our screens this Sunday (26th February), it's safe to say that many fans are wondering just how the beloved long-running ITV drama will wrap up.

We already know that there will be surprises aplenty in store for viewers, but when it comes to Fred Thursday (Roger Allam) and Endeavour Morse's (Shaun Evans) relationship, many of us are waiting on tenterhooks to see how it will end.

Chatting to and other press about the new season, Allam spoke about how there will be "a bit of a crisis" in the Thursday family, especially in regards to his own son Sam (played by Jack Bannon).

He admitted: “I mean, there is a bit of a crisis with Sam. There's my actual son who's drinking far too much this time.

"Well, there's a huge crisis in the family because of the drinking and the chaos that ensues from that. But things are alright with Joan," he continued, referring to his on-screen daughter played by Sara Vickers.

Endeavour season 9
Roger Allam as DI Fred Thursday and Shaun Evans as Endeavour Morse in Endeavour. ITV

The return of Sam in this season is set to be vital to the underlying plot line of the series's finale, with Allam hinting that it leads to things becoming "rocky" between Endeavour and Thursday.

He added: "Unless I tell you the story of the other two episodes, I mean, it is very, very, rocky. And there is something – something goes wrong in it that means that, in the end, results in a kind of parting of the ways for Morse and Thursday. So it's big, it's massive.”

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We know that the beloved father-son-like relationship between our leading investigators has to come to a close, not least because fans will know that John Thaw's Morse never mentions a man called Fred Thursday.

Previously speaking to ITV about the final season, Evans himself admits that Sam's return does lead to a sense of "isolation" for his character going forward.

Sam returns after serving with the British Army in Northern Ireland, but speaking about how his return impacts Fred and Endeavour, Evans said: “We’ve spoken before about the surrogate father and son relationship between Endeavour and Thursday. But in this season Sam, Thursday’s real son, comes back.

"He is not in a great place and needs all of Thursday’s attention. That further isolates and pushes Endeavour outside of that particular family circle.

"Thursday is not his father and Morse is not Thursday’s son. He is on his own. That all offers something interesting and new. Jack Bannon, who plays Sam, is fantastic. It was so lovely to welcome Jack back. He is a brilliant actor.”

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Endeavour returns to ITV1 on Sunday 26th February at 8pm. Seasons 1-8 are available to stream on ITVX now. Check out more of our Drama coverage or visit our TV Guide and Streaming Guide to find out what’s on.

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