Not until 2001 was this long lost episode discovered in the archives at UCLA, a curious place for it to be found, as none of the pre-Emma Peel entries were ever shown in the US during the 1960s. Not only that, but Patrick Macnee's John Steed is totally absent ("The Far-Distant Dead" was the only other one without him), leaving Ian Hendry's Dr. David Keel to carry the story partnered by Ingrid Hafner's Carol Wilson, who barely figured in the other surviving episodes, "The Frighteners" and the recently rediscovered "Tunnel of Fear." Definitely a lost treasure now happily found, it also completes every appearance of three series veterans, Kenneth J. Warren, Edwin Richfield, and Howard Goorney. Dr. Keel spies a female suicide jumping off a bridge to a watery death, only to later discover that the nameless girl actually died from a fatal injection of barbiturates. Perhaps in a nod to Hendry's previous series POLICE SURGEON, we have a police surgeon examining the corpse, played by David Grey (who later did "All Done with Mirrors"). Accompanied by his faithful nurse, the doctor discovers that the dead woman was a trapeze artist for a circus playing its final night in London, where they insist their star attraction is alive and well, her face swathed in bandages since an 'accidental' fall. All the characters are well drawn, acting uniformly excellent, especially Howard Goorney, later to be seen in "The Undertakers," as the Scotland Yard superintendent who fears he may be coming down with the flu (a rare instance for THE AVENGERS where the police are directly involved). Playing the head villain Stefan is Edwin Richfield, who went on to do five more episodes- "The Removal Men," "The White Elephant," "Too Many Christmas Trees," "Dead Man's Treasure," and "All Done with Mirrors." It is Richfield who provides the one obvious blooper, calling the superintendent "Inspector" before quickly making the correction (the old pros simply carry on!). Kenneth J. Warren plays Zibbo the clown, who recognizes Dr. Keel among the crowd awaiting the arrival of Scotland Yard (he later did "Intercrime," "The Little Wonders," and "Epic"). Playing high wire performer Vera Korsova, the fetching Delena Kidd gets to show off her bare legs in a one piece circus outfit. Appearing unbilled is dwarf actor Skip Martin, playing Otto, Zibbo's clown partner; best known for roles in 1961's "The Hellfire Club" (Peter Cushing), 1964's "The Masque of the Red Death" (Vincent Price), 1973's "Horror Hospital" (Michael Gough), and Hammer's 1971 "Vampire Circus," where his evil clown was a frightening visage. Some sources list Nadja Regin ("From Russia with Love," "Goldfinger") playing Anna Danilov, but the less attractive Mia Karam receives credit in the role. Another source lists Patricia Haines playing the corpse of the trapeze artist, but that is clearly not her in the one close-up. As the following 8 entries have yet to be found, the next available episode is number 15, "The Frighteners," our first glimpse of Patrick Macnee's irreplaceable John Steed.