The Bay season 5 ending explained: Who killed Hannah?

As well as digging into the central mystery of Hannah's murder, Jenn (Marsha Thomason) has also had to weather her own fair share of personal problems, as evidenced in the penultimate episode's explosive confrontation with her family.

Coming to a head with the stress of her own family, Jenn didn't hold back in delivering some harsh criticisms of them all, but with her own big workload, could this be the shake-up that the family needs?

Speaking about the emotions of this season, series star Thomason told RadioTimes.com and other press that Leanne Best's performance as Hannah's mother particularly made her teary.

Thomason said: "One of the scenes that comes to mind is when Jenn goes to tell Julie, played by Leanne, that her daughter is dead. We rehearsed it.

"I mean, Leanne is incredible in this series, an incredible actor. But my gosh, in this rehearsal, it was unbelievable. I couldn’t hold it together, I was just bawling my eyes out."

She added: "It’s just such a privilege to be able to tell these stories. People go through this stuff in real life, people really go through these kinds of horrors.

"I enjoy the challenge, I enjoy the emotion of it all. I have a really fun time and I’m completely drained."

But who killed Hannah and what happened to Jenn and the rest of her team? Read on to find out about the finale of The Bay season 5.

The Bay ending explained: Who killed Hannah?

The morning after her big confrontation with her family, things are awkward for Jenn (Marsha Thomason) as she gets ready in her bedroom. She can hear the kids squabbling and chooses to make a swift exit, bumping into her mother Anne (Suzanne Packer) as she does so.

They have a heated confrontation, with Jenn talking about her childhood, the lack of enthusiasm for joining the police and her strained relationship with Anne. But Anne doesn't understand what her daughter means, eventually shouting at her about how hard it was bringing up Jenn.

Elsewhere and back at home, a recovering Tony (Daniel Ryan) returns home with Sinead (Tara Lynne O’Neill), telling her to go to work and not to worry about him.

Back at the station, a recovered laptop has been turned in by a member of the public after it was found in the recycling depot. Completely damaged, DCI Josephine Hardy (Lorna Brown) says they must work out what's on it, whether it was damaged by machinery or an individual.

At home, Erin (Georgia Scholes) is left to consider her options for the future after being arrested for her part in allowing mothers to take things from the corner shop for their children.

Even though she got off with a warning, she's left to think about what she wants for her life and comments that she wishes she was like Jenn, who knew what she wanted to do and went for it.

But Chris (Barry Sloane) tells her that Jenn didn't have it easy, that her parents never wanted her to join the police, and Anne is seen listening in on their conversation, understanding more about her daughter.

Having been arrested and his bail conditions set as not seeing Julie (Leanne Best), Craig (Stephen Wight) comes back to the house to get his things but is met with understandable hostility. He says some parting words to Julie and they go their separate ways, seemingly breaking up.

Back at the station, Lou (Olwen May) finds out from Hannah's laptop that it connected to a router the night that she died. It had already connected to the router multiple times over previous months and again after Hannah's time of death, but getting the details could take a while.

Lou then says that a message was sent from Hannah to Elliot (Max Ferguson) on an encrypted app, telling him that the numbers don't add up and that she was going "to talk to him", with the identity of the person remaining a mystery for now.

They bring Elliot in as a murder suspect but try to find out what he knows. He tells them he deleted all the messages from Hannah because she told him not to tell anyone about what she'd found.

He eventually tells them that the numbers on the containers in the CCTV vehicle footage could be GPS coordinates. Putting them into the system, Lou sees that it places the location as bang in the middle of the bay.

We then find out that the council had been monitoring levels in the bay, testing for impurity in the water. Although the figures paint a picture of a clean bay, Hannah had the details in her possession but shouldn't have had access so must've hacked into the system.

Elliot tells them that he didn't kill Hannah, but at the same time Lou checks the coordinates again and cross references them with the textiles company that Clarkie had previously visited. Nobody's there for them to talk to, but when they look around, they find the same bottles by the bay as they saw in the CCTV footage.

Elliot then tells Jenn that Hannah was going to see her university supervisor Dr David Wallasey (Lex Shrapnel), with Jenn pleading with Josephine to let her go alone as she's already built up a rapport with him.

Once at his home, David tells Jenn that Hannah's laptop may have connected with his router when he would do university sessions from home but Jenn isn't buying it. She arrests him and once at the station, David tells them that he did some consultancy work on the side of his university job.

It's revealed that he was working for Vita Textiles as a consultant. Jenn and Karen (Erin Shanagher) then confront him with the data that he audited for the environment agency and the data that Hannah found.

As she said, the numbers didn't add up, and it looked as though David was interfering with the official figures of pollution in the pipes and waterways around the textiles factory. He was taking backhanders and being paid off to do so.

In a flashback, we see that David and Hannah had a close relationship, and David makes out that Hannah was infatuated and obsessed with him.

Actually, though, Hannah was more interested in getting official documents from David, and was using her close bond with him as a way of obtaining them. That evening, she had come around to his, and when David had left the room to get some wine, he returned to find Hannah reading documents on his computer.

Hannah says she has to leave and tries to run out of his house, but David pulls her back and attacks her. Hannah asks David how much he had been paid off and also tells him that she's spoken to Cal, telling him everything.

David strangles Hannah and kills her, telling Jenn and Erin that he didn't mean to hurt her and that he loved her.

Panicking, he put Hannah's body in the boot of his car and smashed up her laptop. He told Mark about the fact that Cal knew everything, and even though he didn't kill Cal himself, he was partly responsible for passing on the information.

What happens to Jenn and the MIU team?

After the case is closed, attention then turns to the wider MIU team as Erin is called into a meeting with the superintendent. He's been alerted to the fact that she still hasn't apologised to the PC after the vigil unrest.

An investigation into Erin's gross misconduct has now been launched because of her lack of apology, and so she has been suspended until further notice and must pack up her things.

Later, Tony arrives to the station, much to the surprise of the superintendent. Tony tells them that he's been signed off from work for the foreseeable by his doctor and is just there to say hi to the team. He tells Erin that perhaps he could talk to the superintendent about his decision to suspend her, but Erin admits that she doesn't know if her heart is in the job anymore.

Jenn then informs Hannah's dad Steve (Neil Maskell) about the fact that they've arrested David for Hannah's murder, wanting to tell him first. She then goes on to tell Julie (Leanne Best) and Hannah's grandfather Tommy (David Troughton), who thank Jenn for everything she's done for them.

Steve then goes round to see Julie and Tommy, with it clear that they'll all be able to mend broken bridges in light of Hannah's death.

Once Jenn's back in the office, she sees Tony, who tells her that work isn't everything and that he's going to be taking some time off.

Tony's sentiments have echoes of Jenn's own personal life and, fittingly, Chris calls her. Jenn meets up with him and they discuss the fact that she thinks she's gone back to work too soon after her father's death.

She reflects on the fact that Erin's been suspended and Tony is taking time off, wondering if she should do the same.

When she returns home, she finds Anne packing up her bags to leave, and they agree to put in the work to repair their fractured relationship.

We get a small flash-forward to the weekend, when Jenn is enjoying spending time with her family. Conor is going to university, Erin wants to go into social work after doing some volunteering at the food bank and Jenn says she can help her with that, calling on some people she knows. The family seem to be in high spirits – Anne included – as they enjoy a BBQ together.

The Bay is available to stream on ITVX, with episodes airing weekly on Sundays and Mondays at 9pm on ITV1.

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