

Is a creature that can walk up walls clawing to death ruthless and powerful men? Does it have anything to do with Professor Poole's invention of boots that let you walk on the ceiling, or with cartoon superhero the Winged Avenger?
The strange deaths of several astronomers, left bleached white, pose a problem. Whilst Steed joins the stargazers, Emma chases a bright light, and finds herself in the hot seat.