Grantchester's Robson Green says Alphy's "secret" will "fracture" his relationship with Geordie

Season 10 of ITV period drama Grantchester is set to test the relationship between long-serving detective Geordie Keating and new vicar Alphy Kottaram.

The pair got off to a rocky start after the reverend was initially mistaken for a burglar while moving into the vicarage in season 9, which resulted in him punching Geordie square in the face. But eventually, the friction between them cooled to a simmer and then disappeared entirely – and before long, they'd settled into a rhythm that grew into a friendship.

But as revealed by Robson Green when speaking to RadioTimes.com and other press ahead of season 10's UK debut, Alphy has "a secret... [that] really fractures" both his bond with Geordie and his friendships with the people around them.

"When Alphy first turns up, we [Geordie and Alphy] are sat in the pub and I say, 'What's your secret, Alphy?' And he went, 'I don't have one. I'm a strait-laced guy.'

"But Geordie knows there's something. There's a secret and a lie that is haemorrhaging within Alphy and that comes to the surface in season 10, which has a profound effect on their relationship and really fractures that, and really fractures the family of Grantchester, as do the crimes."

Green's costar, Rishi Nair, went on to explain how that is connected to Alphy's love life.

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"Since we last saw Alphy, he's kind of been playing the field a little bit, and I think what it comes down to for Alphy is that he finds it hard to be in a relationship," he said. "I think he is afraid of being in a relationship and settling down with one person because of things that have happened to him in his life.

"But he does want to find someone. He confides in Geordie. He says, 'I want what you and Cathy have.' He does want that. And then eventually he meets somebody that could potentially be that for him. But it's just whether he's in that right place and that frame of mind to be able to give himself to someone else."

Nair went on: "He’s going through a lot in season 10, he has to face his past again and open up boxes that he kind of thought he had dealt with and locked away.

"And so, like anybody when you're dealing with stuff like that, your relationships with the people that you know, like Geordie, are affected, but also with new people. His relationship with this new person that he's met is also tested."

The show's upcoming instalment – which has already aired in the US – is also its penultimate, with Geordie and Alphy once again working together "as a crime-solving duo in scenic Grantchester".

But "they must also support each other through changing times, family struggles and personal secrets", reads the official synopsis.

"Alphy feels like he's found a home, but he’s forced to confront secrets he's kept close to his chest. Will he be able to let anyone fully in, or must he confront truths about himself first?"

Grantchester season 10 will premiere on Wednesday 7th January at 9pm on ITV1. Grantchester seasons 1-9 are available to stream on ITVX in the UK.

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