Anyone reading this issue back in 1971 would have been forgiven for thinking that maybe they'd missed a page or two along the way. The end of "The Creature That Devoured Detroit" was surprisingly sudden, ending with Aquaman destroying a satellite that was causing an algae monster to threaten the motor city but lacking any denouement that suggested that, well, Detroit was OK as a result.
Instead, the story ends with an explosion in space, and the caption "And at that same instant, far from the surface of the Earth..." Was that really the end of the story, never mind the end of the series?
Well... Yes and no. Because, while that was the last issue of Aquaman for six years, it wasn't meant to be. Writer Steve Skeates had planned a second part to the story, and three years later, he managed to tell it. In a Sub-Mariner comic.
No, really; this actually happened, with Skeates just replacing Arthur with Namor and going on as if nothing had happened. Weirdly enough, the issue that completed the storyline, The Savage Sub-Mariner #72 from 1974, turned out to be the final issue of that series, as well. Clearly, comics couldn't handle the idea of an algae monster threatening aquatic villains back then.