From the press release, we learn:

This brand-new series sees a boatload of guest stars visiting the seaside town including Susan George (Straw Dogs), Colin McFarlane (Outlander), Michael Cochrane (The Archers), Melanie Walters (Gavin & Stacey), Vincent Franklin (Bodyguard, Gentleman Jack), Alex Macqueen (The Inbetweeners), Tristan Sturrock (Poldark), Andrea Lowe (Sherwood), Rachel Cassidy (Downton Abbey), Emily Stott (Foundation), Rina Mahoney (Happy Valley), Susan Penhaligon (A Fine Romance), James Clay (MobLand), Kenneth Collard (Cuckoo), Narinda Samra (Ackley Bridge) and more.

What do we know about the stories

New mysteries and puzzling cases await DI Humphrey Goodman and the team in Shipton Abbott. Fact and folklore blur as they investigate the death of a novelist who predicted their demise, a magical night of Dark Morris that soon turns sour, a stolen treasure map that suddenly reappears, and the alleged sighting of a vengeful mermaid lurking out at sea. DI Humphrey Goodman (Kris Marshall) and Martha (Sally Bretton) launch into married life as they search for a new home, whilst Humphrey wrestles with an impossible decision that may change the lives of everyone at the station forever.

Returning to the idyllic coastal town alongside Kris Marshall and Sally Bretton are Zahra Ahmadi (DS Esther Williams), Dylan Llewellyn (PC Kelby Hartford), Barbara Flynn (Anne Lloyd) and Felicity Montagu (Margo Martins), Jamie Bamber (Archie Hughes), Melina Sinadinou (Zoe Williams), Eva Feiler (Lucy Thompson) and Phil Daniels (Marvelous Harris).

We expect this to arrives once the current series of Death in Paradise concludes. We’ll bring any trailer when it’s available.