This story is ironic in a metatextual way, as in a few years Captain Marvel (and his family) would really go to Limbo, when the Fawcett comics closed up shop. There they would chill in the timeless void of fictional characters without a home, until the same company that had caused their titles to be dropped would buy up rights to them and bring them back as secondary characters. (Cap never showed it on the page but he must have been bitter.

Be that as it may, this is a typically charming little tale. Captain Marvel discovers that recent thefts of valuables are the work of the Collector, a wizened old coot who is assigned to take worthless inventions, badly written books, crummy art and such away. (From what I see on sale everyday, he hasn't kept up.) Limbo is a gigantic junkyard. The Collector decides to start confiscating something nice once in a while, just to brighten up his metaphysical realm. This is where Cap takes notice.