A BBC anthology series featuring adaptations of detective stories over 45 episodes in three seasons that ran from 1964 to 1969. As with many BBC programmes made before the early 1970s, many of its episodes no longer exist. Of the eighteen episodes from the first season only twelve are currently known to exist; likewise six of the sixteen editions from the second run are considered lost, and just one of the final ten survives in the archives.

Following an unparalleled series of meteor fireballs plummeting toward Earth, a renowned scientist, his assistant, and an on-target conspiracy theorist race against time to expose a government cover-up, reveal the truth, and prevent a massive meteor from destroying the planet.