According to Fforde, The Big Over Easy is the result of the book Caversham Heights featured in The Well of Lost Plots and includes a possible cameo appearance of the author's heroine Thursday Next, thus verifying this claim.
She hopes to be paired up with Detective Chief Inspector Friedland Chymes, a member of the Detective's Guild with multiple appearances in the fictional magazine Amazing Crime Stories, but instead is paired up with Jack Spratt at the Nursery Crime Department, who is most famous for giant killing and for arresting the serial wife killer Bluebeard.
Jack himself is living with his second wife, Madeleine, who moonlights as a photographer for certain prestigious events, and their five children: Pandora, Ben, Stevie, Jerome, and Megan.
The day after Mary is transferred, Humpty Dumpty is discovered dead outside of his residence at Grimm's Road, apparently having fallen off the wall.
Jack interviews some possible witnesses, including Wee Willie Winkie, the insomniac neighbor; Ms. Hubbard, the owner of the boarding house where Humpty stayed; and Prometheus, the titan from Greek mythology, the latter of which Jack offers to rent the spare room in his house to.
There is another interview at a hospital called Saint Cerebellum's, this time with mad scientist doctor Quatt, and on their way to meeting her Jack notices the serial killer the 'Gingerbread Man'.
Jack had been chasing the killer in previous cases and had to witness his colleague having his arms ripped off, only for the local newspaper, the Gadfly, to say that Chymes had caught the 'Gingerbread Man'.
The conversation ends with Quatt showing Jack and Mary her latest experiment, a kitten's head sewn onto the body of a haddock.
A few days later, Jack and Mary team up with Superintendent Baker, Ashley (an alien who can only speak binary code) and forensic scientist Gretel Kandlestyck-Maeker.
Humpty Dumpty's wife is found to have committed suicide at the biscuit factory, but it is suspected that she has been murdered.
The police of the Nursery Crime Division find a suicide note, but Mary concludes that it was written by his wife by comparing it to her diary.
He was attacked with a large weapon, supposedly a broadsword, and a fifty-pound note was found in his hand, showing he was blackmailing the killer.
Solomon shows them into a room with an abnormally large amount of security: a person going in has to wear no shoes in case of being detected.
In the centre of the room is a puzzle piece, the sacred gonga, held in unbreakable glass.
When an inspector is put in charge of watching Spratt and the others, Humpty's car, a Ford Zephyr, is found.
The woman claims that she killed Humpty out of jealousy by putting three poisonous tablets in his coffee.
Jack is told by Gretel that Humpty Dumpty was shot by someone from behind, which smashed through his shell and burst the albumen, sending a shock which cracked the whole egg.
Jack then remembers a strange doctor, Horatio Carbuncle, who always made living things like the verruca.
They would turn to the only foot care product, made by Randolph Spongg, and the failing company would make thousands.
Randolph puts a sandwich with tin foil inside on a table and shines a lamp on it.
He explains that the sandwich will crumple up under the heat, and when the corners of the tin foil touch, the house will explode.
Moments later, Jack is informed by Gretel that Humpty survived the shot, and that instead, he hatched, because Dr. Quatt secretly fecundated him in vitro.
He is reminded of the axe and takes it and begins hacking down the beanstalk, aiming for the beast to fall down.
Reviewing the book for UK Sunday newspaper The Observer, Peter Guttridge began by writing, "I'm not sure what it says about the mystery genre that pretty much the only unflawed, untroubled, morally unambiguous policeman around is a nursery rhyme character".
The Big Over Easy is great not just because it's very funny (albeit with some excruciating puns) but also because it works properly as a whodunit.
As a conflation of three nursery rhyme Jacks, he has several 'issues' to deal with, including the need for a fat-free diet and a strong compulsion to kill giants."
[4] Reviewing the audiobook edition, read by Simon Prebble, Publishers Weekly found that, "Despite its many virtues, this is probably Fforde's weakest novel, lacking the literary sophistication of the Thursday Next books.