'When Scott Handcock and I took over the reins of Benny's adventures five series back, we wanted to create a set of stories that could be enjoyed one at a time, but with tiny beats and moments seeded throughout that, with hindsight, form a bigger picture,' says outgoing co-producer and director Gary Russell. 'Missing Persons is the culmination of that, as everything we've been drip-feeding in comes to fruition here. Fingers crossed, listeners believe we're leaving on a high, and created a nice level playing field for someone new to come along and take Benny in a direction all of their own. I love Bernice Summerfield passionately and hope we've done her proud!'

The set kicks off with Big Dig by new writer Hamish Steele, where Bernice and her friends find themselves embroiled in an archaeology documentary series gone wrong, as a lost civilisation makes its presence known in a less than pleasant way. Philip Bird (Sapphire and Steel, The Fades) and Paul Copley (Torchwood: Children of Earth, Spare Parts) guest star as Big Dig's long-standing presenters Shepton Rothwell and Jimmy Deel.

The Revenant's Carnival by Martin Day takes Bernice and her son Peter to a masquerade ball on a world ruled by benevolent tyrant Willem van der Heever. Can they head off an assassination attempt, or will Van der Heever's secrets compromise their position? David Warwick (Doctor Who: The Pirate Planet and Army of Ghosts) and Susan Vidler (Amy Pond's Aunt Sharon in Doctor Who) appear as Van der Heever as his associate Doctor Krige.

The Brimstone Kid arrives at the White Rabbit bar in the third instalment, written by David Llewellyn. Bounty hunters galore are in pursuit, and when they hear of the presence of a certain Irving Braxiatel, events take an unexpected turn. Red Dwarf's Mac MacDonald and Doctor Who's John Schwab lead a guest cast including David Menkin (Zero Dark Thirty) and Katharine Mangold (Dark Shadows: Speak No Evil).

The penultimate story in the series - The Winning Side by James Goss - finds Bernice lost in the ruins of an alien world, where she uncovers the story of the great King Theon and his adviser Meriol, and learns the truth of how their world was destroyed by a mysterious sky-witch. Hugh Skinner (Les Miserables, The Confessions of Dorian Gray: The Heart That Lives Alone) and Geoffrey Beevers (The Master in Doctor Who) star alongside Lisa Bowerman in an intimate tale of war and love on a dying world.

'The final adventure - In Living Memory - is a typical Bernice Summerfield story,' says co-writer and producer Scott Handcock. 'It celebrates our magnificent regular cast, wraps up all the loose threads, and tells a frankly bonkers Benny tale all at once… and the script certainly kept our actors guessing right until the very last page!'

Missing Persons will be released on CD and download in September 2013, and will be accompanied by an original novel: Adorable Illusion by Gary Russell. Both are available to pre-order now, either separately or as a bundle at a reduced price.