FRANCES DRUMMOND (Shirley Henderson)
She’s a fragile, damaged soul unhealthily obsessed by Tommy Lee Royce. Staring devotedly at him during prison visits, Frances is the perfect victim/puppet for a manipulative and brutal man whose malevolence stretches far beyond his cell.
Shirley Henderson found global fame as Gail in Trainspotting, Harry Potter's Moaning Myrtle and Bridget Jones's best friend Jude, but has also been a star of the small screen, appearing opposite Robert Carlyle in BBC series Hamish Macbeth and earning a BAFTA TV nod for Channel 4 miniseries Southcliffe.
ANN GALLAGHER (Charlie Murphy)
With her harrowing experiences from series one now behind her, Ann is trying to move on with her life. She knows that she'll never be the same person she was before her kidnapping, but – with the help of Catherine – she's trying to make the best of things.
Irish actress Charlie Murphy is best known for playing the lead role of Siobhan Delaney in RTE drama Love/Hate. She's also appeared in The Last Kingdom, Quirke and '71.
NEVISON GALLAGHER (George Costigan)
Nevison had a tough first series – with his wife terminally ill, his daughter was stolen from him and his friend betrayed him – but with Ann home safe and out of harm's way, he must now must come to grips with the new reality he's forced to live in.
George Costigan rose to fame in Rita, Sue and Bob Too and has gone on to appear in a string of TV shows including The Adventures of Sherlock Holmes, Dalziel and Pascoe and Kavanagh QC.
VICKY FLEMING (Amelia Bullmore)
When her married lover John Wadsworth calls time on their relationship, Vicky Fleming goes on a mission to show him that she's not a woman to be trifled with.
Amelia Bullmore is no stranger to Sally Wainwright's work, starring in Scott & Bailey alongside Suranne Jones. She's also cropped up in BBC spoof Twenty Twelve as well as State of Play, Sherlock and 2014 film What We Did on Our Holiday. Bullmore is also known for her writing, penning episodes of Scott & Bailey as well as plays Mammals and Di and Viv and Rose.
JODIE SHACKLETON (Katherine Kelly)
Her dad is a senior police officer, so Inspector Shackleton must prove she’s worked her way up on merit. Jodie is a sharp, cold and focused operator who grapples with Catherine Cawood’s common sense, instinctive-cop approach.
Another Happy Valley star to make her name on Corrie, Katherine Kelly has gone on to enjoy critical acclaim since quitting the soap in 2012. A leading role in Mr Selfridge has gone alongside BBC4 Kenny Everett biopic Best Possible Taste, The Guilty, The Field of Blood and National Theatre play She Stoops to Conquer.
SEAN BALMFORTH (Matthew Lewis)
This is a man stuck in a dark place in his life. Along with his growing drinking problem, Sean has trouble expressing his very angry, repressed emotions. As things begin to get worse for the West Yorkshire lad, he becomes increasingly out of control.
Known to most as dorky Neville Longbottom in Harry Potter, Matthew Lewis has focused his talents on British TV in recent years, taking roles in Bluestone 42, The Syndicate, Ripper Street and now Happy Valley. He'll also appear in the big-screen adaptation of Jojo Moyes novel Me Before You this June.
AMANDA WADSWORTH (Julie Hesmondhalgh)
A midwife and a working mother, a woman with a faithless husband who’s slowly drifting away from her as he’s swallowed by his secret world. But Amanda's partner isn't the only one with something to hide as she harbours troubles of her own.
Julie Hesmondhalgh bowed out of Coronation Street in 2014 after 16 years playing Hayley Cropper. Since then she's taken roles in Channel 4 series Cucumber, BBC4 film Black Roses: The Killing of Sophie Lancaster and appeared on stage in Blindsided at the Royal Exchange and God Bless the Child at the Royal Court.
CLARE CAWOOD (Siobhan Finneran)
We know Clare is the big, beating heart at the centre of Happy Valley with her sister Catherine. She’s the one who keeps their strange little family on the straight and narrow — but she’s struggling to forge her own life.
Siobhan Finneran's first major role was opposite Happy Valley's George Costigan in Rita, Sue and Bob Too, before going on to appear in Coronation Street and Emmerdale. But to international audiences she's best known as Downton Abbey's scheming O'Brien, a part she departed in 2013. Since then she's been seen in The Syndicate alongside her long-running role as Janice in Benidorm.
NEIL ACKROYD (Con O'Neill)
An old friend of Clare's, Neil is a worker at a local corner store in his new home of Hebden Bridge. When the two cross paths for the first time in years, will they reignite their old flame or will it burn out?
Con O'Neill is best known as a stage actor, winning a Tony Award nomination for Best Actor in Blood Brothers back in 1993. Since then he's starred in a string of productions opposite the likes of Jude Law and David Bradley, as well as appearing on screens in BBC series Criminal Justice, Channel 4's Cucumber and 2013 miniseries The Bible.
WINNIE (Angela Pleasence)
Catherine's neighbour Winnie may look like a little old lady, but she's actually one of the police officer's greatest allies. A willing translator, she's on hand to help when a suspected victim of human trafficking with no English comes calling at the station. But will her efforts put her life in danger?
Angela Pleasance is a veteran of the stage and screen, having popped up in numerous BBC productions in the past. She's probably best known for playing Catherine Howard in The Six Wives of Henry VIII, and younger generations may recognise her as Elizabeth I from Doctor Who's The Shakespeare Code. Horror fans will know Pleasance best for her roles in From Beyond the Grave, Symptoms and The Godsend. Oh and her dad, Donald, played James Bond villain, Ernst Stavro Blofeld, in You Only Live Twice.