The Grantchester finale does not open with a 1950s-era hit; instead, Will talks Baker through the stained glass images in the church. For once, I feel bad for Baker, despite his inherent creepiness, as Will's just narcissistically reflecting on what a screw-up he is. He heads off to see Bonnie, where he does his Will thing, assuming he knows how she feels and telling her what that is, in case she wasn't following his predetermined emotional journey map. Bonnie tells him she and Ernie are heading back home since there's nothing for her here anyway. Will completely misses this is where he's supposed to say "there could be," and rides off to apologize to Wallace.
Larson: That suits your narrative vicar; repentence, redemption. But let's be honest, who changes, really?
Wallace is not impressed and does an admirable of not telling Will to screw off, but Will's guilt-assuaging behaviors will have to wait, as will his prayers for Mrs. C, which she loudly ignores. A body's been found, and unfortunately, it's another vagrant. It's got all the same hallmarks of the previous murders, but it can't be a copycat, as Geordie never revealed those details to the press, which means Robin had an accomplice — or was never guilty in the first place. Geordie and Will pay a visit to talk to Robin, but he's committed suicide. Though Dr. Flemming (Robert Timothy Maskell) says he was responding to meds, the orderly, Kenneth (Callum Sheridan-Lee), admits he told Robin about the new murder that morning, which set him off muttering.
It may not have been the news that drove Robin to hang himself; he had a visitor, and Kenneth's description matches Dr. Larson. She claims he asked her to come and rambled how his victims didn't deserve to die. Will did not meet her in the last episode, since Leonard was Geordie's sidekick, and tells her Robin committed suicide, thinking she will feel bad. Instead, she says he's probably better off, as are his dead victims. As they leave, Will notes Larson has a quote on her wall, "Quod Nocet Saepe Docet." ("What harms often teaches.") He avoids going back to the station since Wallace probably doesn't want to see him and gets his 1950s soundtrack on ("You're Gonna Miss Me" by Connie Francis) while Sidneying up some drink.
Leonard's cafe is jumping, but Leonard isn't paying attention; he's out in the ally counseling those on the fringe of society, like Rosie (Kya Brame), who ran away from an abusive home. She is now trapped because she can't return and get her birth certificate to get a job. His business is a success, but he tells Daniel he can't find joy in it, wishing he could do more for those in need. As it becomes apparent the cafe's days are numbered, they head to see Mrs. C, who is freaking out that Will isn't there ahead of her operation.
Despite Will spiraling, it's good to see Geordie's finally earned Wallace's respect. No more trying to sweep things under the rug; the whole team is on the case. Miss Scott has the victim's personal effects for Geordie to look over, including a piece of paper with Larson's Latin quote, which was in the dead man's pocket. That sends Geordie and Peters back to campus, where they find Larson unconscious. Meanwhile, Will's drinking and wallowing are interrupted by Baker, who just heard about Robin's suicide from Larson. If your creepy sensors do not see where this is going, Larson wakes up and tells Geordie that Baker attacked her.
Baker twisted Larson's claims Robin's vagrants couldn't be helped with his religious fascination and wound up "guiding them to the next life," where they would find a better world. Robin witnessing Baker's killings drove him to his nervous breakdown. He confessed, hoping Baker would stop, and killed himself when he realized he'd failed. As the reality of the danger he's in dawns on Will, Baker goes full messiah, claiming he is God's servant, while Robin and other weaklings, like Will, only talk. As Will tries to convince the kid to turn himself in, Baker starts stabbing him, yelling about Will's drinking, smoking, and having sex. As Will begs Baker to call an ambulance, Baker smiles and says he's helping the vicar as he watches Will bleed out.
Meanwhile, in the world's worst timing, Bonnie shows up to give Will one more chance to ask her to stay, not knowing he's staying silent to save her life. As she marches off in a huff, Geordie pulls up, having realized Baker's next stop was the vicarage. The two race back to save Will, who passes out in Bonnie's arms. Back at the hospital, Mrs. C wakes up, having survived her hysterectomy, and Jack tells Leonard to make the cafe a soup kitchen if that makes him happy. But the bells are tolling, and the vicarage is empty as the show attempts to make us think Will died. (Guys, c'mon.) Of course, he didn't; he's just in the hospital. Mrs. C is praying over him because the fastest way for God to win this standoff was to threaten to take her favorite vicar.
Geordie visits and he and Mrs. C confirm Will's memories of Bonnie being there weren't a dream. But she's leaving today unless Will stops her. That is, naturally, why Geordie is there, car running, and the two race to the train station because, of course, it's a train station. Geordie takes Ernie off for ice cream, leaving Will to beg Bonnie to stay without a primary school peanut gallery. (More's the pity.) Will admits he's not even sure what he's promising, as Bonnie responds she's not posh. He shrugs, reminding her his family's broke anyway. She says she's not sure she believes in God, to which he responds, "That's okay, He doesn't mind." He then drops the L word, so naturally, she does not get on the train. Instead, we get a wedding.
Wait, what? Really? That was fast. Is that Bonnie's dad? Awww, Ernie's so cute! Hey, lookit, Bonnie's charming the Gurney-Cliffords! Tamara's in a hat, hitting on Bishop Aubrey Gray, who looks at her like she's a snack. Mrs. C catches the bouquet and hands it to Daniel. (If only he and Leonard could be next.) At least Mr. Bonnie Davenport gives a lovely speech to end the episode, even if it's not from the pulpit. Also, Geordie and Will are family now! We finally have an excuse to solve crimes together! Guess things really are changing in Grantchester.
All episodes of Grantchester Seasons 1-7 are streaming on PBS Passport.