Deciding to take advantage of Earth's problems, an evil band of aliens called the Space Mafia decide to invade in the mid 1990s. To defeat them, a special covert anti-alien police unit called Blue SWAT is established by the Japanese government. One day, the Mafia attacks Blue SWAT's base and kills them all. Everyone, that is, except three brave heroes. The heroes set up shop on their own and with the help of their allies, dedicate themselves to defeating the Space Mafia.
- Show Narumi/Agent #153, Blue armor: The Hero, very much Hot-Blooded. He later gains a Super Mode called Hyper Show.
- Sara Misugi/Agent #071, Purple armor: The Lancer; a By-the-Book Cop who's also the lone female.
- Sig/Agent #011, Silver armor: The Smart Guy and The Big Guy. Revealed to be an Alien Among Us early on.
- Gold-Platinum, A friendly alien who came to Earth and gave Show the weaponry needed to transform into Hyper Show, but stayed around to help fight the Space Mafia.
- Seiji Usami: The Smart Guy also and a computer nerd; acts as Mission Control for the team on missions.
- Sumire Asou: A naive but cheery girl who works as secretary for the team's "Blue Research" front. Is the only one unaware they're fighting aliens at first.
The Space Mafia:
- Jisp: The Dragon.
- Madamoiselle Q/Queen: The Big Bad.
- Riga, Zodor and Yanimi: Jisps minions, who serve as recurring bosses.
Recurring Metal Hero tropes include:
- Action Girl: Sarah, a tough-as-nails policewoman who's quite adept with a pistol and the de facto leader of the team.
- Cool Guns: The BW-01 Dictator is a Beretta M9 with kibble attached to it. Normal magazine is 10 rounds, comes with an optional 32-round Long Clip, and fires titanium-coated artificial ruby AP rounds that the gun itself then further gives an energy coating. It is powerful and accurate.
- Henshin Hero: Another aversion. The Blue SWAT team have to physically put on their armor, although this gets played straight for Show when he gets his Mid-Season Upgrade into Hyper Show, which involves him being transformed by Gold-Platinum.
- Monster of the Week: Zig-zagged quite a bit. Most episodes see the team having to deal with the same three types of aliens, though some episodes feature a unique alien that the team needs to deal with. Sometimes they work for the Space Mafia, sometimes they are completely independent of the plans. This trope becomes more prominent in the second half after the Retool to make it more like a standard superhero show.
- Transformation Sequence: Another series that averts this. Instead the team have to physically put on their suits.
Blue SWAT provides examples of the following tropes:
- Aborted Arc: As a result of the retool midway through, several plot threads ended up getting dropped or forgotten about.
- Blue SWAT more or less stop trying to keep their Secret War against the Space Mafia a secret.
- It's alluded to early on that the Space Mafia has infiltrated the high levels in society and government, which is why Blue SWAT has to operate underground. This also never gets brought up again after the retool.
- The Space Mafia's master plan turns out to be to crash a meteor into Earth and wipe out the human race, which makes one wonder why they opted for a covert invasion in the first place.
- Aerith and Bob: The names of our trio are Show, which is a fairly common Japanese name, Sarah, a western name that can be pronounced in Japanese, and Sig. Though the last one makes sense, as it's really the name of the alien inhabiting his body.
- Alien Blood: Sig's blood is green. It's the first clue we get that he's actually an alien.
- Big Bad Ensemble: The Space Mafia's leader Queen and her subordinate Jisp. Both have their own separate ambitions regarding Earth and both are needed to be brought down if Blue SWAT is going to stop their invasion. Towards the end, Jisp makes his own play to take over the Space Mafia and briefly becomes the Big Bad, before he's taken out and Queen becomes the Final Boss.
- Body Snatcher: The Space Mafia's modus operandi. Referred to as "Invasion" (in Engrish) in-universe, and is a standard ability amongst Aliens. Staying in one body for too long makes the takeover permanent (as Sig finds out), and if the host is mentally strong enough he/she can exert some influence over their Invaded body.
- Code Name: Averted. The three survivors don't have code names, likely because the size of Blue SWAT would have made it difficult. They do have ID numbers, but use their given names most of the time.
- Cop Show: Takes a much more down-to-Earth approach to the genre than other Toku shows. A lot of episodes see the team investigating a crime or mysterious occurrence that ends up being connected to aliens.
- Darker and Edgier: While it maintains the surrealism of the other series, the more "down-to-earth" tone of the show makes it a more serious and grittier entry than others. At least until it got a retool into a more traditional Henshin Hero show.
- Degraded Boss: Leto, Bona and Kells go from being strong enough to serve as the individual Monster of the Week in episodes to becoming Mooks for other members of the Space Mafia.
- Everybody's Dead, Dave: Our heroes are the last ones left out of their organization after the others were all killed very, very suddenly in the first episode.
- First-Episode Twist:
- The Blue SWAT organization is completely destroyed in the beginning, leaving our Power Trio as the only survivors.
- Sig is revealed early on to be an alien.
- Glass Cannon: For being Metal Heroes, the standard Blue Swat armor is a protective vest and a helmet collectively called the "Protect Gear". The rest of their body is covered in spandex, apparently — in-universe! They make up for it by having really heavy firepower at their disposal. The flip side is that they aren't encumbered with heavy armor, and can move around very quietly.
- Gun Porn: They were very serious about their standard firearm early on, but this was toned down later (probably due to the extra work required to keep model guns in operative condition).
- Hand Cannon: The BW-01 Dictator. It says something when the all-round most effective weapon available to the Blue SWAT team is their handgun, and they've got access to a missile launcher.
- Human Popsicle: When Sig, desperate for a way to move around on Earth without suspicion, took over his current body, he made sure it was that of a brain-dead man frozen for organ donation reasons.
- Idiot Ball: Jisp's entire grand plan in his final episodes is undone because he killed Doctor Aldo after having him install the Mind Control pheromone into him, in order to prevent anyone from getting their hands on its formula, and then left his body right out in the open for anyone to get to it. Because Doctor Aldo is a cyborg, Blue SWAT are able to extract the formula from his computerized brain and develop an antidote. If Jisp had disposed of Aldo's body, or just sent Aldo away on a Flying Saucer instead of killing him, he wouldn't have lost.
- Lighter and Softer: Suddenly turned to this around midway through, for different reasons than Chouriki Sentai Ohranger. Apparently, it was having trouble attracting the targeted child audience (but was doing fine with older fans). As such, more conventional superhero elements were introduced, such as the character of Gold-Platinum and Show getting a Mid-Season Upgrade.
- Locked Out of the Loop: Sumire is initially the only Blue Research member who's not aware of the existence of the Space Mafia. Until she finds out after they kidnap her.
- The Man Behind the Man: Because of how opaque the Space Mafia's inner workings are, it's not clear who's leading them in the beginning. A person who initially seems to be giving orders will often be revealed to reporting to someone else.
- Masquerade: The public at large isn't aware that either aliens or Blue SWAT exist, and both sides work to keep it that way. The Space Mafia does so to keep their invasion a secret, while Blue SWAT does so for more mundane reasons.
- Mid-Season Upgrade: Halfway through, Show gets the power to become Hyper Show from Gold-Platinum.
- Named Weapons: While it's really standard convention for guns to have names, Blue Swat's standard sidearm is the BW-01, codenamed Dictator.
- Odd Friendship: Show is a Jerk Jock With a Heart of Gold who doesn't care much for aliens and is only with Blue SWAT in the beginning for the money. Seiji is a geeky but friendly computer expert who's really interested in aliens. Despite this, the two are shown to get along quite well.
- Oddly Small Organization: Played with. Blue SWAT is initially shown to be a fairly large organization until they're almost completely wiped out in the first episode, leaving Show, Sarah and Sig as the only survivors, who carry on fighting the Space Mafia under that name. They do recruit Seiji and Sumire soon after, but that just brings the total up to five. Lampshaded by Sumire once she finds out."We're fighting aliens with only five people? You're kidding me."
- Really 700 Years Old: 800, actually — although it's unclear if the human body Sig is inhabiting will be as long-lived as he is.
- Retool: The show was made into a more conventional superhero show midway through, with Show getting a Mid-Season Upgrade, the Space Mafia becoming less nebulous and getting a regular HQ, and more Monster of the Week plots.
- Secret War: Both the Blue SWAT organization and the Space Mafia are interested in keeping their war a secret. Blue SWAT because they don't want the Space Mafia's spies to catch on to them and track them down, and the Space Mafia because they're trying to keep their invasion of Earth a covert one. At least until the show was retooled.
- SWAT Team: Blue SWAT are who you call to deal with aliens who regular police can't handle.
- Tomboy and Girly Girl: Sarah is the grounded and tough tomboy to Sumire's cheerful girly girl.
- Soundtrack Dissonance: The opening and ending themes seems way too chill or upbeat for this type of gritty, actionized show.
- This Is Unforgivable!: This is how Show enters his Super Mode, in fact. Whenever the Space Mafia does something he deems unforgivable, his anger allows Gold-Platinum to turn him into Hyper Show.
- Villain Decay: The Space Mafia start the series off a shadowy cabal of manipulators who in the very first episode successfully destroy the Blue SWAT organization. Later episodes see them become a visible Standard Evil Organization Squad who repeatedly fail to defeat three people, continually bicker with one another and ultimately do far more damage to their own organization than to the heroes themselves.
- Weak, but Skilled: Blue SWAT's suits aren't as armored as other Metal Heroes, prioritizing speed and combat over protection.
- What Happened to the Mouse?: One of the female Space Mafia executives flat out disappears from the plot around the show's early stages, despite being just as prominent as her fellow executives in the beginning.
- Who You Gonna Call?: The Blue SWAT team — that is before all but three of them were wiped out in the first episode.