KUALA LUMPUR, Aug 27 — Oh, the ripples that were created when the rights for Felicia Yap's debut novel, Yesterday, were fought for at a pre-London Book Fair auction last year.

I was sure some were on tenterhooks, waiting to see for themselves if the publisher's bet was worth it.

To an extent, it lives up to the hype.

Yap's high-concept thriller takes place in a world where everyone's long-term memory stops working when they're 18, after which they fall into two categories: "Monos" can only remember the past 24 hours, while "Duos" can recall twice as much.

This gives rise to a social hierarchy based on one's memory capacity. Only Duos can hold higher positions, and mixed marriages are frowned upon. There's tension between the two classes.

Electronic devices called iDiaries allow people from the two classes to live as normal a life as possible.

The result is a world where one's history after a certain age is kept in a machine, along with everything else: phone numbers, addresses and important dates. Not too different from our universe.

However, the focus of the novel is a murder mystery, set in an alternate England. The story kicks off with someone called Sophia Ayling furiously ranting at and vowing vengeance against someone.

She also claims that, unlike everyone else, she remembers everything about her past, making her an elephant among goldfish.

A little while later, we learn that Sophia's the murder victim. Could her death be related to her condition?

On the case is Inspector Hans Richardson who has a tendency to colour outside the lines set by the rule books — yes, they have a textbook for cops.

The trail leads him to Mark Evans, a Duo who's a successful novelist and rising star in local politics.

The dead woman is revealed to be Mark's mistress, which threatens his literary and political ambitions and his marriage to his Mono wife Claire.

The plot unfolds through the viewpoints of Mark, Claire and Inspector Richardson, along with the angry, bitter iDiary entries of Sophia Ayling.

Other crumbs of information — some in the form of news reports, document excerpts and quotes — serve as intermissions and additional clues, challenging the readers to find the culprit first (good luck with that).

Soon, we learn that Mark isn't the only one with secrets to hide. Turns out the inspector with the vaguely European-sounding name is a Mono masquerading as a Duo — which means he's not supposed to hold his rank.

He also has less than 24 hours to crack the case before his mind resets, while struggling to hide his true nature from others.

As a whodunit, Yesterday ticks all the boxes. It's paced just right, the plot is focused and the writing is technically solid. Pieces of the puzzle fall into their places at the right time, as if in a tightly choreographed dance sequence.

Not all of it is gloomy, sordid and gory. A few nuggets of humour keep the novel from descending into Scandi-noir levels of cheerlessness. There are nods to real-world tech and companies. The iDiary, for instance, is of course invented by an alt-universe Apple.

We are told, in an intermission, that Mark wrote a "high-concept" novel about our world, which a disgruntled reader pooh-poohs as "far-fetched" and "ridiculous" in a letter to a newspaper — is Yap ribbing her own work here, saving nit-pickers the trouble?

Overall, one is hard-pressed to find something substantial about the novel to critique, beyond what it is ostensibly crafted for. Not to say that it's flawless.

The little asides tend to distract our attention from the crime. The faults in our memories when it comes to recording our pasts and shaping our identities, whether technology can or should compensate... never mind all that. Why is Sophia dead and who killed her?

Also, the potential of the goldfish memory as an obstacle against a dogged investigator is not fully realised here. Some might feel the inspector and his case were never in any danger, as the victim's iDiary is on hand to move his investigation (and the story) along.

What sticks out the most is how little of this world, particularly this quirk of its denizens, is explored. How did this memory ceiling come to be? Does it serve a purpose other than covering up probable plot holes?

Perhaps that's why we sense that this might not be the last we see of the world of Yesterday. The ending leaves a metaphorical door ajar, teasing of more to come.

And more might be on the way, taking the predictable route of the trilogy, with subsequent titles such as Today and Tomorrow. Unlike the twists in Yap's promising debut, many of us probably saw that coming.


Felicia Yap

Mulholland Books

400 pages


ISBN: 978-0-316-46525-0

*Alan Wong is an editor and book reviewer.