Austria is the place where the pastries, the Lippizaner horses, and the international intrigues come from. Circuses, as the ringmaster always says, are for children of all ages. Horses, like dogs, are the eternal reader favorite animals. Soooo....Mary Stewart has taken Vanessa, a young married English veterinarian, to Austria with her seventeen year old cousin Tim, who is running away from his fluffy smother-mother. She is running after her husband Lewis, who was last seen in a newsreel clip with a beautiful blonde at an Austrian circus fire when he should have been in Sweden. Van and Tim find and join the burned up circus, where her professional skill is in demand. Lewis turns up incognito-- and don't forget the Lippizaner horses, where the title comes from (it's the name for one of their fabulous leaps). ""It's all so beastly complicated,"" as Vanessa would surely say, but it's also good lighter than air entertainment. No matter whether Mary Stewart is at the top of her form (and she wasn't in her last-This Rough Magic- 1964), or what charming off-the-tourist track spot she uses for a setting, her melodramatic recreations have a homing instinct for the best seller lists. Guided by the girls, this will fly.