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This volume sees one of the first attempts at an ongoing story for the Legion. The Fatal Five are introduced as deadly enemies for the Legion, recruited in a Suicide Squad-esque thingy where the Legion needs the help of the worst of the worst to defeat a Sun-Eater on its way to the Earth. Famously, it kills Ferro Lad; I might have cared if Ferro Lad had every done anything other than get killed. Unfortunately, he was introduced in volume 5, which I don't have, so he seems pretty much like a nobody here. The Fatal Five is potentially interesting, but like a lot of 1960s Legion concepts, I think later writers will do more with it than its originators do themselves.

Outside of Ferro Lad, it's the usual stupid Legion hijinks. The famous "adult Legion" story comes in this volume, which should really be famous for Cosmic Boy's hairline, and the fact that apparently the marker of adulthood in the 1960s was pipe-smoking. There's also a story where five of the Legionnaires end up as babies, who get adopted by parents from a planet with sterile inhabitants. Even by Legion standards, it's contrived.