The setting is a steampunk Victorian era England. The backstory of the game has some similarities to William Gibson and Bruce Sterling's novel, The Difference Engine, also set in an alternate history Victorian age.

A time traveller on a reconnaissance mission from the distant future became stranded in England of the late 1800s, and his technology came into the hands of the Royal Society led by Baron Fortesque (based upon Charles Babbage), a grand inventor. Fortesque then retro engineered many of the futuristic contraptions, creating an entirely different, alternate timeline.

Baron Fortesque then succeeded in his greatest creation yet - the Chaos Engine - which was able to experiment with matter, and the very nature of space and time. Unfortunately for the rest of the proud kingdom, the Engine then proceeded to become sentient and captured and assimilated its creator, then began to change the countryside for the worse. Vile monsters and destructive automata appeared everywhere, and even prehistoric beasts were resurrected. Telegram wires connecting the British Isles to the European mainland are cut, and any ship attempting to enter a British port is attacked. The British Royal Family, along with members of Parliament and a large number of refugees manage to escape across the sea, bringing with them many tales of horror. The British Empire is left in tatters, and the world in economic and political chaos. This lures a number of mercenaries on a potentially rewarding quest to infiltrate the quarantined Britain, find the root of the problem and swiftly bring a full stop to it.

The introductory sequence is displayed in text on the screen on the floppy disk based Amiga versions, but a slightly modified version is narrated with a voiceover on the Amiga CD32 version, together with some scene-setting animations.

Players choose two mercenaries from a group of six to take on the task of defeating the mad Baron Fortesque and the Chaos Engine itself. The playable characters have various qualities that affect gameplay, such as, speed and combat ability. In one-player mode, the computer artificial intelligence controls the second player, so that one never has to fight the chaos alone.

There are four worlds, each consisting of four levels. The worlds (in order of visitation) are "Forest", "Workshops", "Fortesque Mansion", and "The Cellars", each with its own dynamic industrial music score. The players must traverse through each level, picking up power-ups, gold and keys to pass through the various puzzles and mazes. A number of "nodes" must be activated via weapon fire to open the final doors at the end of the level. Secret routes and hidden items are plentiful along the way. At the end of every second level the player has a chance to spend their collected riches to upgrade their weapons, increase the number of hit points of their character, purchase new items and improve other character attributes. Finally, at the end of the cellars in the hall of machines the players will face up to the Chaos Engine itself in a last battle. Upon its destruction, the narrator of the game is revealed to be the Baron himself, trapped within the machine and studded with implants.

Developers included Steve Cargill, Simon Knight, Dan Malone, Eric Mathews and Mike Montgomery. Joi composed the title theme and Richard Joseph composed all other in-game music.

An early version of the game was previewed on the British TV show Gamesmaster, and some screenshots were featured in Amiga magazines of the time. The early version was reportedly "running on an Amiga 3000" and featured simultaneous three player action.

• SEGA Awards 1994 Best Action Game
• SEGA Awards 1994 Best 3rd Party Game of the Year
• POWERPLAY Multi Player Game of the Year
• Amiga Power 11th best game of all time
• Mega 15th best Mega Drive game of all time.