Detective Sergeant Nicholas "Nick" Henshall was a local police officer. He made his first appearance on 31st December 2008. He returned in 2010 and began a relationship with Katie Sugden and started a fire that killed Terry Woods and Viv Hope. He departed on 17th February 2011 when he killed himself.
Detective Constable Henshall is first seen when he and DS Karen Williams investigate the murder of policeman Shane Doyle and they initially arrest Eli Dingle for the murder and he implicates Debbie Dingle and Jasmine Thomas as being Shane's killers and Henshall and Williams arrest and charge Debbie with the murder. However, Jasmine later hands herself in and confesses to Henshall and Williams that she killed Shane. In February 2009, Henshall investigates the disappearance of Will Wylde and in May questions Cain Dingle about a break-in. He is promoted to Detective Sergeant and returns in July 2010 to investigate the murder of Mark Wylde. He and DC Laura Prior initially arrest Nathan Wylde, but release him without charge due to a lack of evidence. They then arrest and charge Ryan Lamb, but Natasha Wylde is proven to be the killer. In November 2010, Henshall investigates the theft of two horses from Home Farm and he later buys stable manager, Katie Sugden a drink. Katie's ex-husband, Andy Sugden is not happy with Katie dating Henshall and they goad each other. In December 2010, Henshall investigates the disappearance of Jacob Gallagher and he suggests to Jacob's parents Alicia and Justin that they hold a televised appeal. David Metcalfe eventually finds Jacob in an old building and rescues him, despite Henshall telling him to wait.
Katie and her housemates, Gennie Walker and Chas Dingle, receive prank calls and they are later burgled. Gennie tells Henshall that she thinks Andy may be responsible. On a date with Katie, Henshall mentions his dead wife, Alison. When they get back to Katie's, Henshall argues with Andy in the street and she decides to end their relationship. Later, Henshall returns with a petrol can and starts a fire at the back of Victoria Cottage. He tries to ring Katie, but she does not answer and he assumes that she has gone out. Henshall hides and watches as Carl King, Andy and other residents try to put the fire out. The fire spreads and kills Terry Woods and Viv Hope when the Post Office catches alight. Henshall returns the following morning to investigate the fire with Prior and they interview both Andy and Carl. In the coming weeks, Katie and Henshall get back together. Henshall attends both Terry's funeral and Viv's memorial service at The Woolpack. Andy makes a complaint about Henshall harassing him and reveals his relationship with Katie to his colleague Prior. Henshall is then taken off the case and he blames Prior for ruining his chances of promotion. Henshall threatens Andy by holding his face over a gas cooker in his caravan. Henshall and Gennie go to Butler's Farm after Brenda Walker goes to confront Andy. When they arrive, they discover that Brenda crashed her car into Andy's caravan. Henshall talks to Andy's landlords John and Moira Barton and they agree not to press charges.
Colleague Laura Prior warns Henshall to stay away from the case and that she knows that he withheld information from Katie and Carl's statements. On Valentine's Day, Henshall takes Katie for a meal at the B&B and tells her that he is falling in love with her. Andy arrives with Alicia to watch them and Henshall demands that he leave. Henshall asks his colleague DC Darren Foster for updates on the case and Foster tells Henshall that they have CCTV footage from the shop where the phone used to make the calls to Victoria Cottage was bought from. Henshall asks Katie to come away with him and she agrees. At his home, Katie finds some newspaper clippings about his wife Alison's death. Katie asks Henshall about them and he tells her that Alison died in an arson attack on their home. Katie discovers her stolen bracelet and Henshall locks the front door and starts to barricade the house. Katie realises that he is responsible for the prank phone calls, the burglary and the fire. Henshall tells Katie that he tried to save his wife and that it was his fault she died as their home was targeted by some criminals he had arrested and imprisoned. He tells her that he wanted to make up for Alison's death and that he wanted her to need him, so he started the fire at her home in order for him to rescue her. Henshall insists that Terry and Viv's deaths were accidental. Katie demands that he let her go but he refuses, telling her that he loves her and insists that she loves him. Katie tries to escape, but Henshall stops her. Prior and Foster call round to question Henshall after discovering he is responsible for starting the fire and realise that Katie is in the house. Prior calls Katie's phone and Henshall answers and shows them Katie at the window to prove she is alive. He produces a gun and Katie begs him not to use it and he suggests killing them both in order for them to be together. A shot is fired and Katie leaves the house. She tells Prior and Andy, who arrive at the scene with Gennie, that Henshall has killed himself.