One of the five black and white episodes that never aired in the US, "Silent Dust" begins very well, as happy chirping birds expire with great rapidity near a fearsome scarecrow (which is never seen again). The title refers to a new brand of fertilizer which does the opposite of what was intended, killing all earthworms, birds, and even plant life. Its creator has now died, but not before his notorious secret was stolen by a licensed cropduster, Peter Omrod (William Franklyn, later seen in "Killer"), who plots to use it for blackmailing purposes. His henchmen are a particularly nasty bunch, who think nothing of shooting intruders on sight, resulting in a wounded arm for an inquisitive Steed. Jack Watson, later seen in "The Living Dead," plays the sadistic Juggins, who delights in slitting throats (and gets to whip Mrs. Peel), Conrad Phillips plays the rifle-toting gamekeeper Oliver Mellors, Hilary Wontner, later seen in "The Winged Avenger," plays the Minister who introduces Steed to the effects of Silent Dust, and Charles Lloyd Pack, later seen in "You'll Catch Your Death," plays the scientist who worked with its creator. Isobel Black, lovely star of Hammer's "The Kiss of the Vampire" (1962) and "Twins of Evil" (1971), is sadly underused in a nothing part as the daughter of Silent Dust's creator, but Aubrey Morris is well served as a bird watcher who comes to a bad end. For such a deadly serious operation, the climax, a fox hunt on horseback, is almost entirely played for humor, a mistake. Surely such despicable characters deserved a more fitting finale, but there is the novelty of catching Steed astride a noble steed, and Emma, a fox among the drooling hounds. There is one dream sequence showing Diana Rigg in Western garb (1973's "Theater of Blood" still seven years away) that has absolutely nothing to do with the rest of the episode, but she's very funny, as always (removing a bullet the size of a golf ball from an injured Steed). We also get a gratuitous scene where Emma is posing for a bust wearing nothing but a sheet exposing her bare shoulders (apparently, Rigg watching was becoming a favorite pastime in Britain!).
