The Eyre Affair is the story of Thursday Next, Literary Detective with SpecOps 27.  SpecOps deals with the more unusual aspects of crime fighting, and SO27 focuses on busting literary fraud.  Of the other divisions, little is known – their work is highly secretive and dangerous. 

SO5 comes looking for Thursday when Martin Chuzzlewit, a priceless Dickens manuscript, is stolen. Only one man could have pulled it off  – Acheron Hades, a supremely evil villain with apparently supernatural powers.  Thursday is one of the few people who have met Hades and been able to resist him.  SO5 needs her help. 

The attempt to nab Hades goes horribly wrong.  He guns down Thursday’s colleagues, and leaves her for dead.  When she recovers, her explanations of Hades’ shape shifting and mind control meet with extreme scepticism.  But things get even weirder.  Thursday has a visit from her future self, who tells her that Hades is alive and that she must take a LitraTech job in Swindon, her home town. 

Thursday returns to the town she left ten years previously, and soon bumps into her ex-boyfriend Landen Park-Laine.  She met Landen while serving in the Crimea, a messy war now in its 131st year.  He was her brother Anton’s best friend.  Anton was killed in the Charge of the Light Armoured Brigade, which ended in massacre.  Landen’s evidence at the inquest implicated Anton as being partially responsible for the disaster.  Thursday has never forgiven him.  The two are still in love, but Landon is about to get married, and Thursday remains furious with him.

Thursday’s brilliant uncle Mycroft has invented a prose portal, a device that allows people to travel into books.  The uber-powerful Goliath Corporation is very interested.  So is Acheron Hades.  He steals the device, kidnaps Mycroft, and disappears to a derelict hotel in Wales.  When a minor character from Martin Chuzzlewit turns up dead in the real world, Hades’ potential for malicious destruction of the literary classics is all too clear. 

Hades next steals the Jane Eyre manuscript and, using the prose portal, kidnaps Jane.  The much-loved novel suddenly ends on page 107.  But Thursday and the LitraTechs track Acheron to Wales where they find him in cahoots with Goliath, as both attempt to use the prose portal for nefarious ends.  Hades escapes into the Jane Eyre manuscript.  Thursday and Jane leap in close behind. 

Once inside the book, Thursday has to keep Jane and Mr Rochester safe, as well as track down Hades.  She manages to get the Jane Eyre narrative back on track.  Hades, meanwhile, is trapped: only Thursday has the code to get back to the real world.  Hades is bent on the destruction of Thursday, Rochester and Thornfield Hall itself.  By the time Thursday manages to dispatch Hades, Thornfield is destroyed and Rochester is permanently maimed. Thursday can’t bear to leave Rochester to mourn while Jane sails off to India.  She intervenes to change the story’s ending, and Jane and Rochester live happily ever after.

Now Thursday must rush back to real world Swindon.  Her time at Thornfield has made her appreciate true love, and she needs to stop Landen’s imminent wedding.  Fortunately, Rochester lends a hand, and Landen and Thursday are happily wed.