The Deptford Mice Wiki

I am the dark thought in their waking hours, I invade their dreams and bring horror! I am the essence of night, the terror around the corner, the echo behind!

Jupiter (born Leech) was an evil ginger cat, hideous and bloated. He was worshipped as a living god by rats in the sewers of London, who were for centuries unaware of the true feline nature of their deity as he remained hidden in the blackness of a dark portal.


As a kitten, Leech had black fur and green eyes. The runt of the litter, he was bony, scrawny, and ugly. After drinking Dr. Spittle's hair restoration tonic, his fur changed from black to ginger, the fur colour of his murdered brother Jupiter, whose identity he took for his own. During his time in the dark portal, he grew grossly obese, his skin becoming covered with disgusting, pus-filled boils. His eyes also turned red.


From his early years Jupiter had a vicious and spiteful personality, and the cruelty he suffered at the hands of Dr. Spittle only contributed to his hatred for the world. He was sadistic, manipulative, and egotistical.


Jupiter started life as one of three kittens born in London to Imelza, an orange tabby cat, on the 13th of December 1664. His arrival was heralded by a comet that signified a terrible calamity about to befall the world. He was a sickly runt with sable fur like his father, the mysterious Imp. The feline midwife who delivered him recommended that the kindest thing to do would be to kill the weak newborn kitten, but Imelza was horrified at the idea and sent the old cat away.

After a week of winter hardship, Imelza and her kittens were found by William Godwin, the young, unwilling assistant of Elias Theophrastus Spittle. Taking pity on the freezing family of cats, Will carried them back to Spittle's apothecary shop. Though Spittle was at first angered by the arrival of the cats, Will was able to convince him that he could make a familiar out of one of them. The alchemist chose the strong ginger male, whom he named Jupiter. The sable runt he scornfully dubbed Leech because he found him repulsively ugly. Meanwhile, their tortoiseshell sister (who Spittle took no interest in due to her gender) was named Dab by Will.


Leech speaks to the imprisoned spirit of Magnus Zachaire.

Leech grew envious of his brother Jupiter, who began to learn the magic arts from Dr. Spittle. Meanwhile, Spittle would abuse Leech, taking out his anger on him.

After Dr. Spittle had imprisoned the spirit of Magnus Augustus Zachaire in a bottle, Leech learned the magic arts from him. However, he could not use them because only one member of any family is given the right to do so, and Jupiter had taken that right away from Leech. It occurred to Leech that if Jupiter were to meet with some "accident", the powers would then pass to him. He resolved to murder his brother.

Finally, when Dr. Spittle's apothecary shop was burning down, Leech tossed Jupiter down a burning chimney and the cat fell to his death. After this, Leech took Jupiter's name. Beckett the rat led the badly-burned cat down into the sewers, where he crawled into the dark portal and (because he drank from the elixir of life) he was able to remain there for centuries, worshipped by rats.

Role in The Dark Portal[]

All these years, all this time I have lain hidden and secret from my subjects. Think of it - a cat worshipped as a god by rats!
―Jupiter to Audrey

Over three centuries after initially crawling into the portal in the sewers, Jupiter reigned supreme over the rats of Deptford, worshipped as their living god. None had ever seen him, for he dwelt in the shadows of the portal and only his glowing red eyes were ever visible. Jupiter planned to unleash the Black Death upon London once again. To do this, he ordered his followers to dig in underground mines located where plague victims were buried. Through his dark arts, he turned the plague into a living thing that manifested as a deadly vapor that killed any creature it came in contact with.

To be continued...

However, when Audrey Brown confronted the evil cat and threw her mousebrass at him, he fell into and drowned in the sewer water.

Role in The Crystal Prison[]


Jupiter, in the guise of Nicodemus, watches through the tattoo on Akkikuyu's ear as she transforms into a cat.

I must escape. You must help me, I must return to the fields ere I perish for eternity.
―Jupiter to Akkikuyu, as Nicodemus

On a hot day in Deptford, a terrible stench hung in the air. It was strongest at a building site near the River Thames. One of the human builders discovered the source of the foul odour - the rotting body of Jupiter, whose corpse washed up from the sewers. The man who found him lifted his grisly discovery with a shovel and tossed it into the building site's bonfire. A thick, dark smoke rose from the flames and hung over Deptford for two days before a summer breeze blew it away on the third morning.

Meanwhile, trauma-induced amnesia prevented Madame Akkikuyu from remembering Jupiter or any of the events in the sewers of Deptford. Then a mysterious voice began calling to her at night. Only she could hear it and it tormented her. In Fennywolde, the voice finally revealed itself to Akkikuyu as coming from the tattooed face on the rat's ear, which was now animated. It claimed to be Nicodemus, a spirit of the fields trapped in limbo. He begged Akkikuyu to help free him. When the rat agreed, it was revealed that Nicodemus was in fact Jupiter, who had returned from the dead and wanted to take over her body since his was destroyed. Akkikuyu tossed herself on the fire before this could happen, though.

The bonfire spread and engulfed Fennywolde. In the weeks afterward Alison Sedge found Akkikuyu's charred crystal ball. Having lost her mind with grief and still blaming Audrey for everything that happened, Alison angrily threw the crystal ball away and it smashed onto some rocks nearby. Jupiter's spirit emerged and soared into the sky, free at last.

Role in The Final Reckoning[]


The spirit of Jupiter grasps the relatively miniscule Starglass in his huge claws, casting a spell to remove the stars from the night sky.

He is now an Unbeest - an unquiet spirit not governed by the rules of the living. His presence in our world has thrown into confusion all the old prophecies.
―The Starwife, about Jupiter

Wanting revenge against the mice, Jupiter smothered the world in an eternal winter. He stole the Starwife's Starglass, and used this to remove the stars from the sky. He planned to remove the sun the next night, but before he could do anything else, however, Audrey confronted him once more. She threw a snowdrop flower into his mouth, and this condemned him to the doom of life throughout eternity.