A group of carnies are exposed to the moment of death of a famous superhero, and as a result gain superpowers based on their own abilities. Taking the name of the "Cirque d'Obscurite," they make a name for themselves as a deadly group of supervillains, killing the superhero Doctor Camelot. When the rest of his team, the Storm Raiders, track the Cirque d'Obscurite to Devil's Cape to bring them to justice, they are all killed with brutal efficiency. They settle in as enforcers to the Robber Baron, Devil's Cape's resident well-known mob boss.
Around the same time as the Cirque d'Obscurite are rising, Cain Ducett, a young juvenile delinquent, has a run-in with Jazz Rydland, a girl his age with a deep interest in voodoo. When he knocks her down and almost kills her, she curses him, and he soon finds himself morphing into a demonic monster, sending him into a panic that drives him to take hostages, until he realizes the change is gone, seemingly imagined, and reforms his life. He leads a normal, respected life as a psychiatrist, dismissing the incident as hallucination, until twenty-two years later, he suddenly begins to change again and seeks out Jazz to discover that not only was her curse genuine, she made him relapse to force him to protect her - from the Robber Baron himself.
Katie Brauer discovers a secret of her father's several years after his death. He was the late Doctor Camelot, and she makes the decision to become the new Doctor Camelot and bring the Cirque d'Obscurite to justice - especially the Behemoth, who killed her predecessor.
Jason Kale, news reporter, refuses to use his powerful abilities for years, but his twin brother Julian is not as inclined towards restraint. Julian works with their uncle, who works for the Robber Baron himself. After the Storm Raiders are killed, Jason decides to take up the name Argonaut and take on the supervillains and more mundane criminals overrunning Devil's Cape.
Jason, Katie, and Cain all soon meet one another in pursuit of their goals. Upon realizing that they share those goals, they set their sights on the Cirque d'Obscurite. Unfortunately for the heroes, their enemies have been criminals and supervillains for much longer than they have been superheroes, and with greater experience, greater numbers, and the murders of an experienced, practiced team of heroes already under their belts, the Cirque d'Obscurite may be too much for three untested heroes to bring down.
Devil's Cape contains examples of:
- Affirmative Action Legacy: Katie takes the name of Doctor Camelot after her father.
- Always Identical Twins: Jason and Julian.
- Badass Normal: Swashbuckler, one of the Storm Raiders, had no superpowers. None of the Doctors Camelot did either.
- Bad Powers, Bad People: Olena Zhdanov, one of Cain's patients, is capable of rendering anyone a dead, withered husk with her touch, and strengthen herself by doing it. She also thoroughly enjoys doing this, to the point of stopping when she is being broken out of the Holingbroke Psychological Institute to kill an unconscious guard.
- Bad Powers, Good People: Cain is able to shapeshift into a demonic being, complete with claws and batlike wings, and even calls himself Bedlam. He's also a professional psychiatrist who uses his knowledge to talk down an escaped patient and prevent her from endangering anyone else, and after he, Doctor Camelot, and Argonaut defeat the Cirque d'Obscurite, he is the first to step forward and say that they intend to stay in Devil's Cape.
- Big Damn Heroes: Katie's "Uncle" Samuel, alias Sam Small, abruptly drops his Mission Control role when she insists on taking down the Cirque d'Obscurite at the first opportunity. After being blasted and having her armor set on fire and rendered useless, Werewolf arrives to finish her off. He's intercepted in midair by Sam Small moments before he reaches her.
- Boxing Lessons for Superman: Of a sort. Katie initially intends to rely entirely on her Powered Armor, but Sam convinces her to work out, starting with long runs with 70 odd pounds of weight (the same that the armor weighs) strapped to her back. Comes in handy in the climax when her armor's systems get fried by Hector Hell and she has to stumble into the swimming pool on her own strength.
- Cain and Abel: Julian and Jason Kalodimes. Jason seems like the black sheep at first, but when Julian reveals himself as a total sociopath he's firmly cemented as the Cain of the relationship.
- The Cape: Every one of the Storm Raiders, but Doctor Camelot is the one we hear most about. Argonaut also has a dash of this.
- Circus of Fear: The Cirque d'Obscurite.
- Corrupt Cop: Dustin Bilbray, who is both overtly racist, only even attempting to stop a young Cain from doing whatever he wants when he threatens the white Jazz, and who outright demands a bribe to let Jason into the scene of the Storm Raiders' murder. Also Warren Sims, though Sims is much more sympathetic due to his reasons.
- The Cowl: Hangman seems to have been this, but from the sound of it, he went beyond "dark" into "Sociopathic Hero" (and even that might be over-generous; he's implied to have been involved with the KKK). Nobody feels bad when the Robber Baron arranges his death. Of course, if Costas is right, then Robber Baron was the Hangman all along.
- Even Evil Has Loved Ones:
- It's not until Behemoth finds Hector Hell's corpse that he is really enraged by the attacking superheroes, and he comes rampaging out of the mansion holding the body and hunting for the culprit.
- Hector was killed by Scion. His uncle Costas put his father in danger by bringing Zhdanov to his restaurant, so Julian helps the heroes who recaptured her bring down the Cirque d'Obscurite, though only Jason sees him do it.
- Even Evil Has Standards: When the question is put to him, Costas, one of the major figures in Devil's Cape's underground, wonders if he could bring himself to kill his wife in exchange for gaining immortality. He decides he couldn't. The Robber Baron, however, could.
- Evil Uncle: Costas is the uncle of Jason and Julian, and he's a crook who works for the Robber Baron. Of course, part of that is under duress, and later he helps the heroes work against his boss. He's still a crook, though.
- Feel No Pain: Gork, one of the Cirque d'Obscurite, is mentioned as either having this or being in so much pain all the time that further pain makes no difference.
- Flying Brick: Argonaut and Scion are both this type of super, though they use it for different purposes.
- Hero's First Rescue: On what was intended to be a flight test for the Doctor Camelot armor, Katie hears about a collapsed building. While it was unoccupied, she does manage to rescue Bedlam and Argonaut, who were trapped inside when it came down.
- Immortality Immorality: The Robber Baron. He reveals himself to be St. Diable, and that he killed the woman he loved in order to live forever. He began as a pirate, and became a mob boss.
- Incredible Shrinking Man: Sam Small is this. It comes in handy twice, once when it lets him escape the attack on the Storm Raiders and once when Werewolf eats him whole.
- Involuntary Shapeshifting: Initially what Jazz cursed Cain with.
- Karma Houdini: By the end of the book the Robber Baron is no closer to being brought to justice than before and continues to run Devil's Cape's criminal element.
- Kill It Through Its Stomach: How Sam Small beats Werewolf after being swallowed whole.
- Knife Nut: Osprey uses knives designed as extensions of her fists.
- Legacy Character: Doctor Camelot. Katie is the fourth to take that identity.
- Let's You and Him Fight: More justified than most examples. Bedlam meets Scion while trying to track down Zhdanov, and Scion throws him off a building. When Bedlam makes it back up, he spots Argonaut, immediately identifies him as Scion, and attacks him. Jason and Julian are identical twins, and even use the same aftershave.
- Man of Wealth and Taste: The Robber Baron is a pretty classy guy for a remorseless crime lord.
- Meaningful Name: Jason goes by Argonaut. Besides having led the Argonauts, Jason's powers come from a piece of the Golden Fleece, which in the Greek myth Jason and the Argonauts were seeking.
- No Communities Were Harmed: the map of Devil's Cape at the beginning of the book shows that it's in the same geographic location as Slidell, Louisiana.
- Not Wearing Tights: Of the Cirque d'Obscurite only Hector Hell actually wears a "supervillain" costume, with flame motifs and such-like.
- Playing with Fire: Hector Hell's ability, making him one of only two members of the Cirque d'Obscurite who can appear fully normal.
- Powered Armor: Both Katie and her father use this as Doctor Camelot, though the first two didn't.
- Power Trio: Our three main superhero characters are the new Doctor Camelot (Kate Brauer), Argonaut (Jason Kale), and Bedlam (Cain Ducett).
- Reformed Criminal: Cain Ducett is a former juvenile delinquent who's now a respected psychologist at the same reform institute he was once held in.
- Rubber Man: Kraken's power.
- Sequel Hook: Argonaut, Dr. Camelot, and Bedlam all announce their intention to remain in Devil's Cape, and the Robber Baron, though set back by the deaths of the Circe d'Obscurite, is still out there.
- Shame If Something Happened: The Robber Baron wants to do this when Warren Sims comes to Devil's Cape and becomes D.A. Unfortunately, Sims has no one close enough to him for it to work, so the Robber Baron pulls some strings to get Sims to meet his college sweetheart. Once Sims marries her and they are expecting a child, he gets a visit from the Baron.
- Super Senses: Bedlam's other ability, which he retains as Cain.
- Super Strength: Most of what Behemoth got as his superpower. Argonaut, Scion, and Bedlam also have this, though.
- Synchronization: Jason and Julian have this. After Jason is shot in the eye on an outing as Argonaut, Julian calls him demanding to know what he's doing, and why Julian woke up crying blood.
- Take Up My Sword: Katie does this with the Doctor Camelot armor.
- Two Aliases, One Character: "Robber Baron" is eventually revealed to have been only his most recent alias. He's also been known by Saint-Diable, the pirate who founded Devil's Cape, and also Hangman, the creepy vigilante who patrolled the city a generation ago.
- Underestimating Badassery: The Storm Raiders badly underestimated the Cirque d'Obscurite.
- Villain with Good Publicity: The Robber Baron. While he has his talk with Warren Sims, passersby are more excited than frightened to see him.
- Voluntary Shapeshifting: Bedlam's major ability is this. Werewolf is also capable of changing shape - he can appear fully human or fully wolf, but he prefers his third shape, a hybrid of the two.
- Winged Humanoid: Osprey, Bedlam, and the late Winged Tornado. The latter two are both specifically targeted by the former, as Osprey has a vendetta against other superbeings with wings.
- Wretched Hive: Devil's Cape has had this reputation for centuries, and has the nickname of "Pirate Town".
- You Killed My Father: Katie's motivation, although she never tells anyone but Samuel for the sake of her and her father's secret identities.