ďMysterious Doctor SatanĒ (1940), like ďAdventures of Captain MarvelĒ (1941) the following year, owes its existence to Superman. Not just because Superman caused a huge explosion of masked crime fighters in the forties, but mainly because ďMysterious Doctor SatanĒ was supposed to be ďSupermanĒ. Republic had been in negotiations with DC since 1939 for the rights to do Superman but couldnít come to terms with DC. Not being a company that wasted anything, they took their already completed script and simply reworked it with an original masked hero called The Copperhead.
Bob Wayne (Robert Wilcox) goes to see his foster parent Governor Bronson (Charles Trowbridge), who gives Bob a copper metal hooded mask and a handful of small copper metal snake figures. The Governor tells his young ward that his father was the infamous Copperhead, though believed to have been a criminal, he was in fact a man who fought for justice. Bronson says he wished that Bobís father were still around to help him with the scientist criminal Doctor Satan (Eduardo Cianelli). Bob leaves to go think over what he has learned.
Governor Bronson is then visited by one of Doctor Satanís men (Paul Marion) who guns down the man. Just then Bob returns to the office to tell his now dead guardian that he wants to do something to help fight Doctor Satan. Seeing the thug standing over his victim, Bob tears into the man and beats him to a pulp before turning him over to the Chief of Police (Jack Mulhall). Also there is Bobís old friend news photographer Speed Saunders (William Newell) and reporter Lois Scott (Ella Neal).
The man turns out to be wearing a devise with which Doctor Satan can electrocute from any distance if he chooses to. The man is coerced into revealing that Doctor Satan is after the remote control cell invented by Professor Scott (C. Montague Shaw), Loisí father. Doctor Satan has been listening in over a two way devise the man is also wearing. He electrocutes the now useless henchman and heads out to intercept Professor Scott, who is arriving that night on a train.
Bob talks the Chief into deputizing him, then has Speed run him out to the train in Speedís new race car. Doctor Satan gets there first. He gases Scottís compartment, then searches it. Finding a baggage claim ticket the villain surmises that all of Scottís papers and plans must be in the baggage car. He and his confederate tie up Scott and his bodyguard, and then lock them in a closet.
Just then Bob enters the compartment. Satan passes himself off as Professor Scott, and Bob says he is in danger of being attacked by Doctor Satan and he wants to be there to catch him in revenge for Governor Bronsonís murder. Doctor Satan smiles and pulls out a gun. He tells Bob he is in fact Doctor Satan and then shoots Bob with a poisoned needle. Satan tells his henchman to retrieve Scottís papers from the baggage compartment and then leaves.
Bob gets to his feet, the copper mesh mask he had in his inside coat pocket had stopped the needle. Putting it on, he climbs out a window and travels along the roof of the train to the baggage car. Swinging inside he beats up the henchman, leaves him with a copperhead figure in his hand for the police to find, and returns the papers to Scott unseen.
Scott plans to demonstrate his remote control cell to the military using his own yacht. After seeing the yacht off he returns home where he discovers his control panel is missing. Doctor Satan emerges from the shadows and informs the startled scientist that he has taken the control board. He has also had a bomb installed on the yacht. If Scott doesnít hand over his plans for the cell, Doctor Satanís men will explode the bomb at ten oíclock. Reluctantly Scott opens his hidden safe.
Just then The Copperhead comes in through the French doors and gets the drop on the criminal scientist. He gives Doctor Satan a choice, either call his men and tell them not to explode the yacht, after which he will be turned over to the police, or The Copperhead can just gun him down where he stands. Doctor Satan agrees to make the call, but it is just a trick to get next to the lights. Kicking the plug out causes the room to be thrown into darkness. Satan tries to grab the plans from the safe, but it is booby trapped with an electric current and he is knocked unconscious.
Seeing no way to stop the explosion that is less than twenty minutes away, The Copperhead jumps into his car and speeds toward the docks. Grabbing a motor boat he races out to the yacht and jumps aboard to inform everyone that the boat is about to explode. Everyone gets off just before the yacht is blown up.
When Doctor Satan doesnít return, his men go to Scottís home and rescue their boss from the police. Doctor Satan already has another plan formulated. He will get the cell when Scott next tests it in an airplane.
Bob asks Professor Scott if he can be in the plane in case Doctor Satan tries anything, but Scott tells him that wonít be necessary. Bob sneaks aboard anyway and hides in the back while Scott demonstrates how he can maneuver the plane by remote control. Doctor Satan tries to use his stolen control board to take control of the plane but discovers that Scott has changed the frequency on the cell. He quickly dispatches one of his men to get on that plane.
Taking up another plane a henchman makes a dangerous midair transfer from one plane to the next. Once aboard he cuts the fuel line. Bob puts on his mask and emerges from the back of the plane. Engaging the man in a fight, The Copperhead throws him out the door to his death. The cut fuel line causes the plane to lose power. Without power the cell has no control over the plane and The Copperhead is able to safely land the plane. Once on the ground he removes his mask and returns it to his pocket.
Doctor Satanís men had been following the plane by car and open the door expecting to find their confederate and are surprised to see Bob instead. Grabbing him and the cell, they take the captive hero to one of their hideouts in the country side. Putting a guard on him, Stoner (Walter McGrail) goes to report to Doctor Satan. While his guardís back is turned Bob gets the jump on the man and knocks him unconscious.
Grabbing the manís gun, Bob puts on his mask and goes upstairs to hunt for the master criminal. The Copperhead finds Doctor Satan and his men in a room, examining the remote control cell. Getting the drop on them, The Copperhead has all of the men stand against the wall while he backs up to a phone to call the police. This spot just happens to also contain a death trap; it is wired to electrocute men who have failed Doctor Satan. The evil scientist goes to flip the switch but the masked hero is two fast for him. The Copperhead shoots the switch, shorting out the machine.
A fight erupts in which the cell is destroyed. Seeing that he is out numbered, the Copperhead makes his escape by jumping through a glass window. He quickly hides in the trunk of one of the cars so that when the villains get outside, they think he has gotten away. Jumping into their cars they drive to another hide out, this time in the city.
Before getting out of the trunk, the Copperhead overhears which floor they are going to. Not wanting to draw attention to himself The Copperhead climbs up to the floor on the outside of the building (yes I know that sounds ridiculous, but it is a perfectly acceptable and even logical move in the serial world). He overhears Satan planning to try and get the cell that is still in the sunken yacht. Just then The Copperhead is spotted and has climb up to the roof where he engages in a shootout before jumping onto the roof of a neighboring building and sliding down the elevator cables (sans gloves, ouch!) to the ground floor and getting away.
The Copperhead informs Scott of Satanís plans. Scott moves fast and gets a diving bell and a demolition crew out to the site of the sunken yacht. Lois and Bob go down in the bell, where they direct the ship how to place the explosive charge to completely destroy the yacht and the remote control cell inside it. Doctor Satanís men board the ship and try to take it over by gunpoint, but a fight breaks out.
The ensuing scuffle causes the explosive charge to be set off with the diving bell still under water. The force of the explosion weakens the structure of the bell and water starts to pour in. Luckily an air pocket forms inside the bell giving Lois and Bob a brief reprieve from drowning. Back on board the ship, the fight isnít going well for the bad guys. Stoner pulls a gun on Speed and takes the man hostage, enabling them to get off the boat. Once the bad guys are gone, Scott has the bell returned to the surface just time to save Bob and Lois as the air was almost gone.
Later back at Scottís estate, everyone is shocked to see a drugged Speed walk in with explosives strapped to his chest. Doctor Satanís voice emits from a speaker on the explosive charge. The group is informed that if Speed is not given the plans for the cell, Doctor Satan will blow up Speed in front of them. Bob has Scott try and stall while he goes into another room and calls the Chief. He quickly convinces the Chief to have all power to the city cut so that Doctor Satan canít explode his bomb. What with hospitals and such, the Chief can only give him thirty seconds.
Scott gathers his papers and starts to leave with Speed while Bob follows. Once out on the grounds, the power to the city is turned off. Timing it perfectly, Bob cuts the straps holding the bomb to Speed and throws it out into the middle of the yard. When the power comes back on Doctor Satan explodes the bomb but no one is injured. Stoner and the men have been waiting just outside the gates and see everything. They rush in and start beating the crap out of Bob. Seeing this as their big chance, they grab Scott and push him into their car.
Bob rushes out into the street and fires several shots at the fleeing car, puncturing the gas tank, which doesnít explode, but just leaks gas (a serial convention). Running to his car, Bob puts on his mask and heads out in pursuit. He easily able to trail the thugs by following the gas leaking from the hole he put in their tank. When the car runs out of gas, Stoner steals a fuel truck, a vehicle not known for being inconspicuous. The Copperhead easily catches up to the gas truck as it heads up into the mountains. Stoner isnít as big a fool as he seems. He has Scarlett (Lynton Brent) climb to the back of the truck and open the spigot, pouring gallons of gasoline on the road behind them and then igniting it. The Copperhead is forced to dive out of his car right before it roars into the flaming inferno and exploding.
Stoner takes Scott to a dock side hideout. Leaving Scarlett to guard the scientist, Stoner goes to get Doctor Satan. Scott attempts to pay Scarlett to helps him escape, but Scarlett shows him the device that Doctor Satan has put on of his men that allows him to electrocute them anytime he wants. Scott proposes that if he can remove the devise Scarlett will help him escape. Scarlett agrees. Scott successfully grounds the devise and removes it. Doctor Satan arrives and Scarlett pulls a gun, planning to use Doctor Satan as shield to get him and Scott away.
Doctor Satan is not so easily caught. Pressing a button on the panel behind him he summons his robot, which grabs Scarlett from behind and crushes the man to death. Doctor Satan reveals he can only control his robot for short distances but with Scottís remote control cell, he will be able to build an army of robots he can control anywhere and take over the world (Bwa Ha Ha!). He threatens to turn the robot on Scott if he doesnít build another cell for him. Scott reluctantly agrees, saying that Satan has all of the equipment he needs except for a special tube that is only carried by one manufacturing firm.
Meanwhile back at Scottís estate, Lois is telling Bob all about the tube as well. Realizing that Satan will need a tube if he is to have Scott build him a cell, Bob goes and stakes out the shop that sells the tube. Spotting Stoner, Bob lets him buy a tube and then follows him to the hideout. Putting on The Copperhead mask he attempts to sneak in but is caught by Corwin (Kenneth Terrell). The have massive fight until The Copperhead knocks his opponent for a loop with a punch that would down a camel.
Doctor Satan has his hideout wired for sound and has over heard the fight. He ties Scott to a chair and puts a gag on the man. Seeing a shadow in the glass window of the roomís door, Doctor Satan shoots the man through the window. The Copperhead falls into the room, dead. Doctor Satan pulls the mask off and discovers it is really Corwin. The Copperhead enters the room wearing a bandanna to disguise himself with. Having Doctor Satan stand with his back to him, the Copperhead puts his own mask on and then proceeds to untie Professor Scott.
Doctor Satan calls his robot and then drops through a trap door. Startled by Satanís disappearance, he doesnít notice the clanking robot sneak up behind him until it starts to squeeze him to death. The robot walks out onto the roomís landing to crush The Copperheadís spine against a post just to add insult to injury. Luckily Scottís bonds have been loosened enough for him to finish the job. Rushing to the control panel, he shuts off the robot, which promptly drops The Copperhead into the bay. The cold water revives the masked vigilante, who quickly swims back to the dock only find that Doctor Satan has escaped with both Professor Scott and his robot.
This is probably one of the best serials Republic ever produced, which is amazing when you consider itís mish mash of plot elements that combine sci-fi horror and a masked hero with a mad scientist who acts more like a gangster than anything else; not to mention a director that had little enthusiasm for the project (William Witney hated robot). It is a testament to the professionalism of Witney and English that a film they both have stated to not liking was still well made and exciting to watch.
The serial gets off to a rollicking start after a talky opening with Dave Sharpe, doubling star Robert Wilcox, diving across a room to jump on the assassin of the Governor. From that moment on the serial is fifteen chapters of nonstop action as the heroes and villains fight and chase each other with only small breaks to recap the plot and catch their breath. The fights are very inventively staged with one of the best being in Chapter Eight where the stuntman doubling William Newell comes stumbling out of a closet with a bucket on his foot and has to contend with it while trying to duck punches and deliver a few of his own; itís funny and exciting at the same time.
The rest of the stunt work is equally as good with the hero making some spectacular leaps from high places into speeding cars, transferring from one vehicle to another, and an odd moment where the hero makes like a human fly and climbs up the outside of the building (an obvious hold over from the original Superman script where the Man of Steel would have simply flown up to the window). The best stunt is preformed not by a stunt person but supporting player Dorothy Herbert, a trick rider hired because she could perform a Cossack Drag. A Cossack Drag is a maneuver where the rider swings off the saddle to one side of the horse, hanging backwards off the horse and using their legs to hold on, the rider then has both hands free to fire a rifle at their pursuers. Herbert does this maneuver during Chapter Eight and it looks spectacular.
The special effects are what fans have come to expect from a Republic serial; lots of exploding buildings, exploding cars, exploding planes, and exploding boats; all done with huge gouts of flames erupting into the sky. But the big draw of ďMysterious Doctor SatanĒ was the robot. Sure it looks like a large water heater with arms and legs, but the film makers actually manage to make such a ridiculous looking prop menacing as it clops slowly down dimly lit hallways after the hero.
The acting is a bit lopsided. Robert Wilcox, a good looking guy, seems to have almost no personality. Though blessed with a deep rich voice, he does almost nothing with it, most lines coming out as slightly above a husky whisper. His leading lady Ella Neal is only slightly more engrossing, most of her performance is a one note expression of over the top fear of the villain.
Luckily supporting players William Newell and C. Montague Shaw are on hand to keep the dialogue scenes from being monotonous. Newell is perfect at playing the bumbling but enthusiastic side kick. He is amusing without being annoying as way too many comedy relief characters tend to be. This is best shown during the fights where canít seem to handle himself too well, and usually gets the stuffing kicked out of himself due to his clumsiness. His performance is so ingratiating that when he has a bomb strapped to him in Chapter Four you feel real concern about his safety.
Good old Monty Shaw is an old pro at playing both a heroineís father and a kidnapped scientist. He gives a solid performance with just enough personality to be interesting without distracting from the other players. He is especially good in his scenes with the villain.
But nobody could upstage the real star of the piece, Eduardo Cianelli. Not only is he given all of the best lines, the lighting is always set to make him look as evil as possible, and he knows just how to use them to their best advantage. Unlike most villains, he does very little ranting at his men, preferring instead to use a softly voiced implication rather than an actually voiced threat. With the exception of two scenes where he loses control and screams at his men out of frustration with the masked hero; he is usually calm, cool and collected, making his attempts to kill various members of the cast that much more frightening. Cianelliís Doctor Satan is one of the most unique and greatest villains to ever grace the serial movie screen.