According to the Operation Luna liner notes, this serial drama program was the last BBC radio broadcast to outdraw the television audience on the same night. The first of the three original series (“Journey to the Moon”) centered on a crew of four, rocketing to the moon in 1965. The first time travel occurs in the 11th episode where they find themselves displaced on Earth by thousands of years. Eventually, they return to their own time.

Almost all of the recordings of that first series were destroyed, but most were rerecorded for a rerun series (renamed “Operation Luna”). Those rerecordings are available on CD along with the non-time-travel second series (“The Red Planet”) and third series (“The World in Peril”).