The title of this episode kind of gave away the plot. Aerial photographs from 200 feet up..."feathered spies"...gee, you don't suppose that they could have been birds, do you?

Using blackmail to force the hapless pigeon fancier to work for the bad guys was very realistic.

It was rather interesting that Matthew did most of his work at normal size for this episode. I liked hearing him cap Father Unwin's Shakespeare quote, and then complain that he was getting cramp from sitting in the tree.

During the "chase" scene, it was funny hearing Father Unwin tell Matthew to hang on, because he was going to speed Gabriel up to 50 mph!

It was amusing to see Matthew interact with Krueger the Great Dane, but it's not plausible that a tiny guy could outrun a long-legged dog. They should have had Matthew slowly backing away, while the dog considered the situation, and then a final short sprint to the bush.

I thought that the inside intelligence man was going the question the notion that pigeons would be bombing the plane, but he didn't. It was the other man who, being told to bring the plane back into the hangar, faced the camera and said something like, "And this man is supposed to be from Intelligence." I notice that he did obey orders, though.

The bomb release was by remote control, and Matthew had gotten hold of the remote. I realize that this would have eliminated the nice noisy explosions that are a staple of Supermarionation, but wouldn't it have been more sensible to just let the pigeons fly home, and unstrap their little camera bombs?

It was a nice touch that Father Unwin did not look at the evidence used for the blackmail, but if he didn't look at it, how could he have been certain that it was the evidence? He might have handed over blackmailing material on some other poor sap.