Humphrey and Martha's wedding day has finally arrived…and now they've come face to face with the lavish affair organised by Anne. But such a big day seems to have come all too quickly, and Anne's plans feel far grander than anything either of them actually wanted.

Meanwhile, there's no rest for the Shipton Abbott team. They have to deal with the theft of a valuable museum piece and a nefarious pair of cyber criminals before they can join in the celebrations.

With bride and groom running around, and thieves running amok in Shipton Abbott, can the team wrap everything up in time to mark Humphrey and Martha's long-awaited union, or does fate have other plans?

On the open ground of Abbott Moor, an early-morning walker stumbles across a chilling sight: a woman, face down on the ground, with an arrow straight through her shoulder. The victim, Niamh Kirby, didn't see her attacker, and there's no trace of their presence or weapon at the scene.

As the team dig deeper, they uncover a family feud between Niamh and her brother-in-law. She accused her brother-in-law of murdering her husband, who vanished from Shipton Abbott overnight a decade before, and the bad blood between them has never settled. With answers lying in the past, they find themselves with more than one crime to solve.

Meanwhile, other plans are afoot; with the wedding fast approaching, Anne dives headlong into the planning, but Humphrey and Martha worry that she might be a little too invested in their fairytale ceremony after her recent romantic entanglements. Esther wrestles with unexpected consequences when a white lie she told Zoe about her dead father comes back to haunt her.

When a priest from a Catholic boarding school suddenly disappears, Humphrey and Esther find that his case has uncanny similarities to a local myth – ‘The Devil on the Rocks'. Why was he last seen marching on a nearby beach in the middle of a dense fog, and where is he now?

With the school's headmistress reluctant to aid the investigation, a large sum of money missing from the school safe, and the priest nowhere to be found, the team have their work cut out trying to pin down the truth.

Meanwhile, Zoe helps Martha clean up Ten Mile Kitchen after a break-in, but it's clear she's hiding something. Anne's new flame helps her move onto the Lily Bond as Humphrey and Martha take over her house, but is there more to Richard than meets the eye? Eager to please, Kelby ups his game when Margo suggests his job may not be secure.

A fishing trawler heads out to sea with three brothers and their ailing stepmother aboard. When it returns to Shipton Abbott harbour several hours later, only the three fishermen remain. A note found on deck suggests the woman took her own life. As her estranged daughter comes to town to help make funeral arrangements, the simple case grows more complex.

Meanwhile, it's the day of the house visit, but it's no plain sailing for Humphrey and Martha. Will the houseboat hit the mark or be an obstacle in their path to fostering?

A clairvoyant predicts unusual events that begin occurring in the life of a recently bereaved woman. The team starts to suspect that the psychic's powers might be too good to be true, as the woman starts ending up in more and more dangerous situations. When the team discover a connection to her deceased grandfather, everything begins to fall into place.

On the home front, it's a big day for Humphrey and Martha, as they have their fostering interviews. Can they show their social worker Hannah how much fostering means to them, or will their nerves get the better of them?

As a steam train races through the Devonshire countryside, Humphrey and Esther join the Shipton Abbott Players for a murder mystery rehearsal. Though Humphrey is only playing a detective, things turn from amateur to professional when the actor playing the victim is found dead with a real knife in his back.

Life begins to imitate art as the pretend suspects become all too real, and the steam train is scoured for genuine clues. With the victim barely known to his fellow performers, and the whole group under suspicion, the team sets out to unravel a dark past that reveals hidden connections between the actors.

Meanwhile, love is in the air as Humphrey and Martha enjoy date nights and Anne throws herself into the world of online dating. But has she bitten off more than she can chew? And it's all change for Humphrey and Martha as they start a new chapter in their lives, embarking on the process of becoming foster parents.