(Zip Comics 001, 1940)
Shortly after giving himself super powers, Steel Sterling gets word of a brutal bank robbery in the town of Beeville and sets out to bring the culprits to justice. Determining that the crooks must have been guided by a mastermind of some sort, he trails their plane to a mountaintop fortress.
The bow-wielding guards outside the Black Knight's fortress (spoiler: it's the Black Knight's fortress, but what were you expecting) are notable for being the one time that he has anything related to his chosen theme around, and even they are supposedly only there to prevent... mountain cops?... from hearing the sound of gunfire. Inside, it's plain old gangsters.
Gangsters armed with ordinary machine guns are of course no match for a man with all the properties of steel, and Steel Sterling quickly makes his way to the Black Knight's throne room, where he is immediately dropped into a deep pit full of rats.
I'd just like to take a second here to appreciate the fact that the Black Knight's costume is a) 100% brown and yellow with no black at all and b) a pretty conventional super-person getup aside from what appears to be a leather jerkin or similar. Historical, yes, but not particularly knightly.
A pit full of rats is also not enough to stop Steel Sterling, and he makes his way out, causes the Black Knight himself to fall in, and sets out after the fleeing gangsters just in time to avoid a secondary deathtrap as the fortress explodes behind him. The Black Knight is finished, it seems.
The Black Knight is not, in fact, finished, and is soon (Zip Comics 002) hard at work robbing gold and fur shipments coming out of Alaska. Though he manages to capture Steel Sterling when he infiltrates the villain's fake iceberg base he does a bad job of coming up with a suitable deathtrap for the hero and ends up in the hands of the US Navy.
Steel Sterling's next case brings him to the South American nation of Brazonia, where a man called Dr Yar has taken the famous scientist Walter Cummings in order to force him to develop weapons of war and help conquer the gold-rich country.
Dr Yar is of course eventually revealed to be an alias (or possibly the real identity?) of the Black Knight. Just why he has abandoned his old moniker is unstated but perhaps it is as simple as a desire not to attract the attention of Steel Sterling again. His new look is at least still visually interesting - particularly the periscopiscopes, which are of course goggles which allow 360 degree vision.
Dr Yar really leans into the scientist aspect of his new identity, and deploys gadgets such as: flying tanks, oil bombs, electric rays and various viewscreens and visualizers.
Plus: he not only has Alligator Men at his disposal but also a swarm of giant mosquitoes straight out of an ad for a pest control company (being big does not help them bate through steel skin, alas).
Once again the Black Knight/Dr Yar apparently meets his end, and this time it's explicitly at the hands of Steel Sterling, who stuffs him into the barrel of his own super-howitzer before it fires. A truly brutal end, even for a dedicated super-villain. (Zip Comics 003, 1940)
Steel doesn't have to live with any guilt he might feel for long, however, as the Black Knight returns in the next issue, this time climbing the rungs of the aristocracy from mere knighthood to become the Radium King. His new plan is simple: steal the entire US radium supply and then ransom it back for 30 million dollars.
The Radium King has appropriately impressive digs: an underwater base in Lake Superior that would probably be pretty hard to find if one of his minions hadn't blabbed under threat of a beating from Steel Sterling.
The Radium King costume turns out to borrow heavily from the original Black Knight getup, although without a lot of the yellow elements. I'd say that it's better than the Dr Yar outfit but not as composed as the original, and that the half-mask/mustache combo is particularly unpleasant. Speaking of Dr Yar, the Radium King reveals that he survived Steel's attempted cannon execution by simply crawling back out of the cannon.
Not to be robbed of a kill, Steel Sterling uses the Radium King's own submarine to blow him and his base to high heaven. Surely he's dead this time! (Zip Comics 004, 1940)
Not quite! The Black Knight's fifth and final appearance (under the original name, this time) is probably his most ignominious, though it does feature his cool underground city headquarters, seen above. In it, he engages in a campaign of sabotage, kidnapping and extortion against his former kidnap victim/current minor member of Steel Sterling's supporting cast Walter Cummings, who has gone into the munitions manufacturing game and has gotten the contract to produce the mysterious Zeta Ray for the US government. Somehow, if the Black Knight can delay production of the US Zeta Ray for long enough then his own scientists can produce one for him and that will be good, and if that description seems vague to you then I must assure you that it is 100% accurate to the comic. I don't even know what the Zeta Ray does, for heaven's sake.
Though Cummings' first factory is destroyed and his second collapses due to some sabotaged cement, Steel Sterling steps in and has almost completed a third when the Black Knight decides to take a personal hand and ram a tanker truck full of TNT into it. Now here's the embarrassing part: not only does Steel Sterling handily prevent the truck from destroying the factory, but the first time that he is even aware that the Black Knight is involved in the plot against Dr Cummings is when he spots him just one fraction of a second before he is atomized in the explosion. It's not even as dignified an end as being shot out of your own cannon would have been. (Zip Comics 005, 1940)
