Marriage, the forthcoming BBC One comedy drama, will star Nicola Walker and Sean Bean.

Written by Mum and Him & Her creator Stefan Golaszewski, the four-part series is described as "an up-close portrait of a marriage - sometimes funny, sometimes moving, always revealing."

The series focuses on married couple Ian (Bean) and Emma (Walker) as they negotiate the ups and downs of their 30-year marriage. "We see them dealing with the insecurities, the ambiguities, the hopes and the fears that are part of all marriages, as the drama explores the risks and the gifts of a long-term intimate relationship."

Sean Bean says: "I'm thrilled to be playing opposite the talented Nicola Walker and I'm looking forward to bringing Stefan's intimate scripts to the screen."

Nicola Walker comments: "This is a unique project. Stefan has created such a beautiful, funny and complicated world and I'm excited to be stepping into Ian and Emma's marriage with Sean."

Stefan Golaszewski, who will also direct the show, adds: "It's amazing to get to work with Sean and Nicola. They're actors of such depth, truth and warmth and I can't wait to go on this journey with them."

Beth Willis, executive producer for production company The Forge, says: "Stefan's exquisite observation of marriage is funny, warm and searingly honest. His writing is a joy to read. I cannot wait to see Sean and Nicola bring to life this wonderful couple."

BBC commissioner Piers Wenger says: "The extraordinary depth and complexity of Stefan's characters calls for two of our most talented and loved actors. Enter Nicola and Sean. It's always a privilege to have you on the BBC."

Filming will begin shortly on the four hour-long episodes, and transmission details will follow in due course.