An alien army from the Fifth Dimension has invaded our solar system. Led by Bosc the Terrible, they have already conquered Uranus, and their next target is Earth. Only the great Captain Blasto can stop this invasion and free Uranus.
Blasto provides examples of:
- Ain't Too Proud to Beg: Upon defeat, Bosc tries to bargain his way out of what's coming to him by trying to bribe Blasto with riches, promises of power, and women. The last one momentarily tempts Blasto, but he ends up refusing Bosc's offer.
- Alien Blood: The aliens spew green when their heads explode.
- Big Red Button: Pressing a large button with the sign "Do Not Press" displayed above it will result in Blasto getting disintegrated by a lightning bolt. In a slightly later section of the game, a second, identical button is encountered, with the same "Do Not Press" sign. If, against all logic, you fall for the same trick and press this one... a bunch of health and powerups spawn nearby.
- Big Bad: Bosc the Terrible is the major threat of this game.
- Boisterous Bruiser: Blasto is very cocky, but his survival skills are not put into question.
- Captain Space, Defender of Earth!: Phil Hartman voices Blasto, who plays this trope straight for comedic purposes.
- Card-Carrying Villain: Bosc specifically refers to himself as "an evil tyrant" in the final cutscenes.
- Damsel in Distress: Every so often, you can rescue babes that are stranded in dangerous areas, rewarding you with health if you reach them.
- Expy: A diminutive green alien in red with a high-pitched voice, mastery of war technology, and ambitions of galactic conquest? Are we talking about Bosc the Terrible, or [[Western Animation/Invader Zim Invader Zim]]?
- Idiot Hero: Blasto is rather dimwitted for an action hero.
- Little Green Men: Bosc and his minions are all this.
- Minimalist Cast: If one doesn't count the enemies, bosses and babes, there are only three main characters: Blasto himself, Admiral Bigshot and Bosc.
- Mister Big: Bosc the Terrible, the main antagonist, commands an army of alien invaders, but is comically short.
- Naked People Are Funny: In the final two levels, Blasto loses his space suit and ends up saving the day in little more than his mask and some tight red briefs.
- Rape, Pillage, and Burn: Parodied in the opening cutscene, where Evil Overlord Bosc announces that his plan for the invasion of Earth is to "enslave their women, eat their children, and rape their cattle."
- Raygun Gothic: The setting takes heavy inspiration from this aesthetic.
- Retro Rocket: Blastos main ship is one of these.
- Taking You with Me: Bosc sets his fortress to blow once it becomes clear he won't be able to defeat Blasto, or tempt him over to his side.
- Top-Heavy Guy: Blastos upper torso to lower body proportions can only be described as preposterous even by top heavy standards, with a hugely exaggerated chest, shoulders, and biceps, but comically tiny hands and legs... and that chin. Even with his stance braced for balance, you get the feeling he's going to tip over any second now.
- Uranus Is Showing: The game is set on Uranus for the express purpose of making these jokes.Admiral Bigshot: Blasto! Uranus is in big trouble!
Blasto: What did I do this time?
- We Can Rule Together: Part of Bosc's pleas during his Villainous Breakdown. Blasto isn't interested.