Perplex City's most venerable institution and (most of the time) home of the mysterious Receda Cube. The Academy tutors young academics in the art and science of puzzles. It also plays host to the PCAG and many other cultural events, overseen by Master Sente Kiteway.

Anna was the matriarch of the Cube Retrieval Team - and is now sadly deceased. She suffered the loss of one of her oldest companions, the chief librarian, Isaac Cymbalisty. In her blog, My Writing, she recounted her determined investigation into his 'suicide', which led to the revelation of Miranda Katsoulis as his murderer. Sadly, Anna herself became a victim of the Third Power on 29 July, 2006.

Who was 'Combed Thunderclap', and why were they writing this Library of Babel site? (Well, actually, we do know now - but why spoil the surprise?) It seems that CT took the Cube from Perplex City to Earth.

This religious cult worships the Receda Cube as one of the physical forms of divinity. Their practices are generally well meaning and generous, though they have a strong proselytizing faith - in other words, watch out or they'll try and convert you. They also have shocking taste in web design.

A pharmaceutical company specializing in cognitive enhancement products - in other words, pills that make you smarter. Their most popular product is Ceretin, much favoured by the people of Perplex City, though they also make a number of other drugs enhancing different mental functions. Cognivia is also heavily involved in medical research and in drug testing at the PCAG.

The governing body of Perplex City. This nine-strong group is elected by the public and often make the headlines. Political infighting between members can distract them from their daily tasks of calculating budgets, planning developments, and improving the citizens' quality of life.

Established by Sente Kiteway, the Cube Retrieval Team was made up of seven highly intelligent Academy scribes. Their job was to co-ordinate the hunt for the Cube - but they also tended to conduct their own investigations out of hours...

The Receda Cube is a powerful and enigmatic object. Worshipped and feared in equal measure, it has been at the heart of Perplex City's culture for centuries - even if nobody quite understands where it came from or what it can do.

And now, the Cube is lost - buried somewhere on Earth. Who will find it first? Will they be lured by the reward, or by the Cube's formidable power?

The Receda Cube is stolen from the Perplex City Academy. A guard is killed in the process. The Academy's Master, Sente Kiteway, sets up the Cube Retrieval Team (CRT) and traces the Cube to Earth. He contacts Earth directly for the first time, asking for our help - and offering a large cash reward.

Sente's elder daughter, Violet, discovers that Bernardo Holyoke has been murdered and that he might have been involved in the theft. Her search for clues leads her to the Cube-worshipping Reconstructionist cult, where she discovers that Aiko Entrescore (of the CRT) was a member. Aiko is cleared by the police.

Pietro Salk, of the Perplex City Sentinel, is contacted by an anonymous source. She calls herself The Advisor and claims to have been employed to steal the Cube, alongside Bernardo Holyoke, someone codenamed 'C' and their leader, the psychotic 'V'. Pietro is murdered before he can establish The Advisor's identity.

With the help of Violet's sister, Scarlett, Earth's Cube Hunters gain access to Pietro's secret files. They lead to an apartment in Ascendancy Point and to a name: Monica Grand. The Cube Hunters persuade Pietro's widow to meet Monica face to face - but too late. Monica has been brutally murdered by V.

Chasing a lead from Pietro's notes, Violet researches a sinister ancient society called the Third Power (with Kurt McAllister's help). It seems that the Third Power are still very active - even turning up on Earth in a dramatic helicopter stunt. Meanwhile, Scarlett heads off to chase another clue: an unmapped place named Viendenbourg.

Violet's Third Power research leads to an antique diary that she can only access if she's a published author - so the Cube Hunters start writing a book for her. On the way to Viendenbourg, Scarlett meets Allain Castille, a young man searching for the same place. After a dizzying encounter, Scarlett ends up in hospital and Allain vanishes.

Scarlett discovers that Allain was looking for his mother, Claire, who had disappeared from Viendenbourg months before. Viendenbourg, it seems, is a military research facility. Scarlett sneaks in and finds Allain, whom she helps to escape. What she doesn't realise is that Claire Castille is C, the last member of the Cube theft crew.

Kurt investigates the Third Power and has a run-in with the police. He and Violet work out that V was once a sound engineer at Hesh Records - they even find a recording he made of Monica Grand's murder. Meanwhile, Scarlett and Allain head further north to find Claire.

Violet's diary research is halted by the death of Chief Librarian Isaac Cymbalisty. The police call it suicide; Anna Heath, his best friend, calls it murder. Could it be related to the diary? Up in Anjsbourg, Scarlett and Allain finally track down Claire Castille - 'C' - who confirms that the thieves never held the Cube. But it's Kurt who finally identifies Cymbalisty's murderer. It's his own girlfriend, Miranda.

Having deceived Kurt, Miranda goes on the run. He enlists Violet's help and together they chase Miranda from town to town until she heads off into the mountains on foot. Kurt - now dangerously obsessed with hunting her down - follows her to an underground hideout and confronts Miranda in a final, fatal face-off. Violet arrives to find Kurt sitting by Miranda's body.

Following Miranda's death, Violet, Kurt, Anna and Scarlett begin to work together. They even involve Caine. Sharing their information, they start to get a clearer picture of the mystery behind the Cube theft. It seems that thefts at the Academy are not so unusual... equipment has been vanishing regularly for months now. Tracking a batch of stolen items, the conclave split up - and Anna ends up dead.

Since Anna's death, the Third Power seems to be a more and more powerful threat. They attempt to destroy the data link with Earth and successfully create a portal to transport a handful of agents to our world. But even the so-called good guys have a lethal edge to them: Scarlett kills a man, and the Academy is found to be conducting deadly experiments as they attempt to build a new Cube. Sente's involvement drives a wedge down the middle of the Kiteway family - and ends the career of Council Leader Camryn Scott. The new Leader, Nathan Earlywine, immediately restricts the data link, screening all communication for 'dangeorus or subversive' information. No more messages from the conclave, then...

The new Council Leader censors all communication between Perplex City and Earth - but that doesn't stop 'Combed Thunderclap' updating their Library of Babel website with clues as to the Cube's location. At length, an intrepid Cube Hunter puts the clues together and digs up the long-lost treasure - and the story behind the theft is revealed.

This cutting-edge music company was the first in Perplex City to release an album on Earth: the acclaimed The Silver City, by Viard. Other Hesh artists include Roll for Damage and, in the past, Joya. Hesh has also made the news for less artistic reasons - their playboy boss, Helix Hesh, has enjoyed a series of tawdry affairs; and they once employed a sound engineer called Cyrus Quinton, aka V, who's murdered a few people.

If it's headline news, you'll find it here. This is where we put all the most important developments.

Call him a geek. He won't argue with you. But there's more to Kurt than cryptology and number crunching. Racing around in the dark and chasing conspiracy theories, he's almost become, well, heroic. His Earth-facing blog, The Path of Least Time, gives a modest version of his exploits. But has any of this caught Violet's eye...?

A UK-based games company enlisted by the Academy to help in the search for the Cube. Mind Candy works with the Academy and the PCAG on Earth, publishing puzzle cards, running live events and recruiting thousands of players. Their staggeringly attractive and intelligent staff are also unexpectedly modest.

The website and blog of Caine Johannson and his rock band The Ooze. Caine was a member of the Cube Retrieval Team and in his spare time he drummed, played a bit of guitar - and double-crossed his freinds...

The Perplex City Academy Games (PCAG) is an organization as well as an event. The annual Games are the puzzle equivalent of the Olympics, with top puzzlers vying for the prestigious PCAG title. The PCAG committee has as strict anti-drugs policy, which is enforced with the help of Cognivia. Recently, PCAG-sanctioned events have started being held on Earth.

The Perplex City Banking Corporation - not only the city's largest financial institution, but also notable as the former employer of Monica Grand. Their takeover of the Fivebridge & Remton Consolidated Bank foundered when Grand was brutally murdered.

This is the basic podcast category index. Please visit the main Perplex City Podcast page for more information.

The Perplex City Police Department, run by Chief Eoin Morgan. After the Cube's disappearance, civil unrest was definitely on the rise. There was also an unprecedented spate of murders (most likely perpetrated by a man known as V). Leading the undercover investigation was Detective Helena Frye...

Or the 'Recons', as they're popularly known, are a Cube-worshipping cult that broke away from the more placid Brotherhood of the Six. Their aggressive cupidity for the Cube led to them being prime suspects when it disappeared - indeed, eight of them were detained by the police. Aiko Entrescore - a member of the Cube Retrieval Project - was outed as a Recon shortly afterwards.

Pietro Salk was a victim of his own success. An investigative journalist, his integrity and protection of his sources were renowned. That's why The Advisor asked him to act as an intermediary between her and the police when it became clear that her life was in danger from V. Alas, Pietro got caught in the firing line and was murdered by V first - but not before leaving an intriguing maze of clues. His wife, Sylvia, still mourns his premature demise.

Like the fever, Scarlett is infectious. Younger sister to Violet, she's an enthusiastic adventurer with hopes of becoming a journalist. As far as she's concerned, all this Cube business is about the most exciting thing that could ever have happened, ever.

But just recently, Scarlett has been forced to grow up a little. Digging into the city's past, she's uncovered a few disturbing truths about her world's history - and suffered as a result.

Sente is Master of the Perplex City Academy. The Cube was stolen from under his nose and he was determined to get it back.

Having traced the Cube as far as Earth, Sente came up with a controversial plan: to enlist our help by turning the hunt into a huge, enthralling puzzle. Was it a brilliant strategy? Or an attempt to hide the truth?

As well as being a stern and mysterious pillar of the community, Sente is also father to Violet and Scarlett Kiteway.

The city's most popular newspaper, which now publishes an Earth edition online. The journalists of this esteemed organ have played an active role in the hunt for the Cube - most notably Pietro Salk (now departed). Not only does the Sentinel carry all the latest news from Perplex City, but it also features letters and articles by readers based on Earth.

You can access their main archive here.

They're a mixed bunch at the Sentinel: tabloid hacks and gossip-mongers on the one hand, and pioneering truth-seekers on the other.

Monica Grand (RIP), aka The Advisor, was a member of V's Cube theft crew. Her day job was as an economic advisor at PCBC. When Bernardo Holyoke was murdered, Monica realized V was eliminating anyone who could identify him - and that's when she turned to Sentinel journalist Pietro Salk for help. Unfortunately, V found out and murdered both Pietro and Monica (the latter rather brutally). Her last moments were witnessed by Pietro's wife, Sylvia.

A secret society known to have existed for hundreds of years, with an unhealthy interest in controlling the Cube. Their operatives are thought to be on Earth as well as in Perplex City, and often occupy prominent social positions. V is believed to be a senior member, though even he is not the top man. Since the Cube's recovery, the organisation is thought to have been destroyed... but will they ever truly be wiped out?

We don't know a lot, but we know this much about V: he's a killer and he tried to steal the Cube. One by one, he's been bumping off the members of his crew - first Bernardo Holyoke, then Monica Grand, with a few more casualties along the way. His real name, as far as we can tell, is Cyrus Quinton, but even that may be an alias.

His job at Hesh Records allowed him to indulge his quirk for taping murders. But perhaps more horrifying than all this is the knowledge that even V has a boss - as yet unidentified.

Violet shunned the usual academic channels, instead preferring to apply her mind to more exciting challenges - such as poker. This helps to supplement her librarian's salary, paying for a glamorous apartment out on the Mobius Strip. Her taste for adventure sometimes gets her in trouble, though...

Though she talks tough, Violet has a soft spot for Earth. She even writes a blog, Quirky Acuity, just for us. She also worries about her sister and wonders what her father is up to. And as to what she thinks of Kurt and Caine... well, you'd have to ask her.

Perplex City purveyors of fine ice cream, produced by cows that are bred for their high IQs. This intelligence is apparently passed on to whoever eats their dairy delights. The Whipsmart website is wonderful, but beware - the music can prove to be infuriatingly infectious.