BBC R4 Drama - Anthony Price's 'The Labyrinth Makers'
Adapted by Nick McCarty
Directed by Hamish Wilson. 
Broadcast 1980 [can anyone help with the exact date?]
Coded from tape at 128/44.1

Discovery of a crashed WWII plane means that a botched
investigation and a search for missing ancient artefacts
come alive again.

Very plausible sub-plot about Stalin's pre-WWII purge of
many of the Red Army's officers.

This production is thirty years old, but it's still fresh
and almost undated. It's sound quality is good too.

Cast
John Stride
Paula Wilcox
Mark Coleman
Peter de Sousa
Michael McKenzie
Alan Manson
Sandy Neilson
Neil Peckham
Raymond Ross
Lawrence Ruddick
Ian Sexon
Pat Williams