Today marks the 104th anniversary of the birth of Lester Dent, a/k/a Kenneth Robeson.
Not exactly a household name these days, eh? But in his time, which occupied a substantial chunk of the first half of the last century (he died young, in 1959), Dent was one of the most prolific and most successful writers on the planet. And it all came from a single character, the protagonist of — according to Wikipedia — 190 novels to date, and scads of stories. (Nearly all the books are credited exclusively to Dent, with the majority of the others, even those published long after his death, giving him at least partial credit. The “Kenneth Robeson” whose name actually appeared on the covers, though, was just a pseudonym.)
That protagonist: Doc Savage.