You can listen to the whole thing here. From the website:
For most of us, codes are riddles wrapped in enigmas wrapped in mysteries. Even the Saturday crossword or Sudoku can be a stretch. Yet we’re surrounded by codes everyday, whether it’s a puzzle in the paper, the GPS on our Smartphones, or every time we browse the internet.
Initially stumped by that most common—and frustrating—of codes, a cryptic crossword clue, writer Sunil Badami finds himself surfing an internet ‘Wikislide’: discovering the connections between code and poetry, evading shadowy government agencies, and ending up in the murky corners of the dark web, where he’ll try to unlock the secret to one of the Web’s most intriguing and eerie mysteries.
Riddle. Mystery. Enigma. takes you on a journey from the familiar to the unexplored, through the mysterious history of cryptology and coding, and how it affects our lives today. Part radio documentary; part radio code breaking exercise; definite radio goose chase. Plus you get the opportunity to solve our own intriguing secret code, encrypted into the episode.
Yes, this is secret coded radio. Keep your ears open, you don’t want to miss anything.