That night, when Skulduggery and Valkyrie are standing on the roof of Bespoke Tailors he tells Valkyrie that Serpine killed Skulduggery’s wife and child before his eyes, and when, in a rage, he reached for a dagger, he never suspected Serpine had coated it in poison. He then reminds Valkyrie of the advice Gordon gave him in his will: that sometimes the key to safe harbour was in plain sight, and explains that he believes the brooch given to Fergus and Beryl to be the key to the caves. He tells her that she must get the brooch from them. Skulduggery continues into the Caves, soon coming across Serpine, having just found the Sceptre, with a group of Hollow Men. The Sceptre starts to ring as he approaches and fights Serpine. He sets Serpine on fire and batters him, but his injuries heal themselves in seconds. Valkyrie runs out of the shadows and rams into Serpine to stop him killing Skulduggery with the Sceptre. They are forced to flee, chased by Serpine and his Hollow Men. When they are outside Gordon’s house, Tanith helps fight off the Hollow Men. Serpine destroys the Canary Car using the Sceptre. A car pulls up, with China and her assistant in the front seat, and Tanith, Valkyrie and Skulduggery jump in as the car speeds away. Valkyrie fights Sanguine to save Guild's family. Neither win, but Sanguine promises to keep out of Ireland. When the gang return to the Hibernian, Valkyrie kisses Fletcher, and they are now a "boyfriend-girlfirend thing". In June 2011 Landy posted on his blog that he would be writing a short story about Skulduggery called The End of the World. [29] It was released in late February 2012 to coincide with World Book Day 2012. The Australian release of this novella came with an additional short story titled Just Another Friday Night. Deleted scenes from Skulduggery Pleasant were included. It is set a few months after Death Bringer. It was included in the 2014's short story collection. The trio goes to Maybury's house, but no-one answered the door. When Geoffrey has only 15 minutes until he is going to be eaten. Skulduggery finds a door in Maybury's bedroom. Geoffrey notices the carpet is wet and soggy. Skulduggery calls out to Maybury through the door, but nothing happens. Geoffrey asks where the water is coming from, but Valkyrie says there is no water. Geoffrey sees a fish but he is the only one to experience it. Skulduggery looks for a way to open the door, without noticing it, he does. The go down a room with a dead Maybury sitting in the armchair. Geoffrey panics, but Skulduggery tries to calm him by telling a useless story.

During the fight with Serpine in the Sanctuary, Stephanie glimpsed her True name in the Book of Names but could not remember it before the Book of Names was destroyed. Skulduggery destroyed Serpine with the Scepter, breaking the Scepter's power in the process. Afterward, Skulduggery offered to take Stephanie on as his assistant and apprentice because she is a descendant of the Ancients. Stephanie decided to take the name of Valkyrie Cain. Skulduggery is questioning Kenny with Valkyrie about Paul Lynch's death. He uses the name, "Detective Inspector Me", while his façade is on. They leave along with Fletcher Renn when they finished and Skulduggery drops Valkyrie off at Alice's christening. They meet Chabon the next day, who manages to swindle them with a different skull rather than Skulduggery's. Realising the con, they chase him through the streets of Dublin and pin him down, asking him about the real skull. Chabon reveals that Davina Marr, the new Prime Detective, had bought the skull for triple the price just that morning. A new plan is made to steal Skulduggery's skull from the Sanctuary. Set between Mortal Coil and Death Bringer, the novella Apocalypse Kings was published in February 2021. As Lord Vile, Skulduggery is a master of Necromancy and can bend shadows to his will. He was strong enough to hold his own against Darquesse and even could've killed her if she hadn't healed herself in their showdown. He can summon spears of darkness, absorb death to make his armour stronger, create ropes of shadows, and use them to rip any people who try to pull off his armour. Lord Vile was even able to hold out against Kitana Kellaway and her friends who's powers were close to those of Argeddion himself.Valkyrie and Skulduggery travel to Roarhaven to visit the new Sanctuary. Before they do so, Valkyrie saves an American tourist family from a horrible shopkeeper, who happens to despise mortals. Valkyrie and Skulduggery reach the Sanctuary and meet with the Council of Elders where they discuss the apparent Death Bringer, Melancholia. Ravel agrees to provide any resource needed to know more about the Passage. It's not destiny. Even if it was, I've changed it. It's not happening." — Valkyrie telling a Remnant she has sealed her True Name, Skulduggery Pleasant: Mortal Coil Finally, Vile and Darquesse battled in O'Connell's Street, Dublin; Eason's Book Shop and Forbidden Planet, a comic book shop. They manage to return to their normal selves in Forbidden Planet.

From 2007 onward, he took on Valkyrie Cain as an apprentice Detective and together they have saved the world many times – most notably when two of the three generals returned, the Faceless Ones almost broke into our dimension (after which he was trapped in another universe), Croke Park Stadium was almost destroyed, a Remnant infestation of Ireland, the Death Bringer almost killing everyone, Argeddion almost destroying the world by giving Mortals magic, the War between Sanctuaries – in which almost every Sanctuary in the world declared war on Ireland – also almost killed everyone, Valkyrie succumbed to Darquesse, making him draw together a team of soldiers, monster hunters, killers, criminals and Valkyrie's reflection to defeat a god. Skulduggery explains that the only person able to create an illusion is Robert Crasis. They drive to Crasis' house, and he explains that Foe threatened his family so he was forced to disguise Mercy as Francine. Skulduggery asks for a map, and he finds the location of the Doomsday Machine.We have mysteries to solve, and adventures to undertake, and I need my partner looking dapper at my side." — Valkyrie to Skulduggery after agreeing to return (in reference to a line said by Skulduggery in the first book) Midnight Three-hundred years before the story begins... the story begins. Set in Tuscany, Italy, 1703, during the War, Hell Breaks Loose focuses on an enraged Skulduggery, 13 years after being killed with his wife and child by Serpine and resurrected as a living skeleton, and three years after his five years as Lord Vile, as he and the Dead Men hunt down Serpine and Vengeous, the Generals of Mevolent. The story follows Valkyrie and Skulduggery going to America to investigate a witch. It introduces the concept of "Horts", essentially people outside of the fictional universe who consume entertainment (that is actually real in the fictional world) and have choices as to what happens. The Guardian then explains that if Skulduggery wins the fight against him he may activate the Meryyn Sigil and the one who wears the Sigil will be invincible until all the sand falls in the hourglass.

Valkyrie is sent to investigate Jerry Houlihan who has come up with the idea that he is a butterfly (he's not). It is revealed that Jerry is just one of the many mortals who were suddenly developing magical abilities and were all constantly threatening to reveal the magical society to the general public. Later Solomon Wreath approaches Valkyrie who angrily tells him that Guild has given all the credit of the victory to Mr Bliss. Wreath tells Valkyrie that she can still save Skulduggery by using his original skull as an Isthmus anchor. With new hope, she is also told she is a natural at Necromancy, seeing how skilfully she was able to wield Wreath's cane. Wreath offers to train her, as she will need more power to get through her new mission. There is evidence that Skulduggery speaks the Irish Gaelic language (commonly known as Gaelige or Celtic Gaelic). In Mortal Coil he mentions the word creim, which is Irish for erode.The Wonderful Adventures of Geoffrey Scrutinous: (5–6) Set after Mortal Coil, Geoffrey Scrutinous and Skulduggery Pleasant search for Elwood Satchel. Originally included in Mortal Coil.