Grantchester season 8's opening episode ends with devastating moment for Will

"From the moment we first met Will, he's always been struggling with his demons," he said of the reverend and motorcycle enthusiast. "What drives him in life is being the best man he can – everything he does, every case he helps Geordie with, every problem that he solves, he feels like he's getting better and better as a person, morally. And then this thing happens that just seems to erase all of that in one instant.

"Everything he's worked so hard for is gone just like that. It just destroys the way Will thinks of himself, because this action, whether it was an accident or on purpose, in the eyes of God and everyone else, he believes it's unforgivable, and it really sets him down a dark path."

And just before the credits in the opening episode, the accident occurred.

Read more:

• Grantchester's Robson Green teases "defining moment for Geordie"
• Robson Green addresses Grantchester's future: "Long may it continue"

Prior to that life-altering moment, Bonnie decided to return to her parent's home following the news that her mum had collapsed due to a stroke – a decision that Will didn't support.

"You shouldn't have to, you're seven months pregnant," he said.

"Yes, pregnant. Not a porcelain doll. Stop vicar-ing me," she responded.

When Will made a dig about her stepping away from Tuesday bible group, they continued to bicker, with the couple leaving things on frosty terms as her taxi drove out of the village.

After previously promising Ernie that his bike was on a "long holiday" following a spate of unsettling incidents, including a minor crash earlier in the episode, Will had a change of heart and headed out for a ride to blow off some steam.

And that's when it happened...

As he rounded a bend, the bike collided with a man who had stepped out into the road, sending Will and his motor skidding along the ground. Fortunately, he wasn't hurt, but the same couldn't be said for the pedestrian.

Will ran over to him, begging the man to wake up as he checked his pulse, but there was no response.

"Now that this thing has happened, he's questioning whether God or anyone can ever love him again," said Brittney. "He just shuts them out and it pushes him further and further away from everyone to the point where we don't know if he's ever coming back."

Thankfully, Geordie will be on hand to support his friend through one of the most testing periods of his life, just as Will has helped the detective previously, but will he be able to overcome this latest hurdle?

We already know that Brittney is exiting the series to "focus on new projects". His character is approached with a "life-changing offer", which he can't resit, which opens the door for "charismatic" vicar Alphy Kotteram, played by Rishi Nair (Hollyoaks, Count Abdulla).

But does this tragedy also contribute to Will's decision to leave his life in the village of Grantchester?

"The tragedy of this series is that everybody thinks they're losing the Will that they love, and Geordie has to watch it happen while also trying to deal with his own issues with his job, and possible retirement," said Brittney.

"Geordie doesn’t realise how far down the path Will goes."

Grantchester is available to watch on ITV and ITVX. You can order the Grantchester Mysteries books by James Runcie from Amazon.

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