What is the name of the fourth book of skulldugery pleasant?

Answer 1

Skulduggery Pleasant: Dark Dayshere is a summary from Wikipedia:

The novel starts with a sorcerer named Dreylan Scarab being released from an American prison in Arizona. When released, Scarab meets up with Billy-Ray Sanguine saying that he plans to destroy the Irish Sanctuary and requests help to do this. Sanguine suggests that they set up an organisation known as "The Revengers' Club"(that consists of past antagonists such as Dusk and Spring-Heeled Jack to destroy those who wronged them. The targets being: Skulduggery Pleasant, Valkyrie Cain, Thurid Guild and Tanith Low.

Valkyrie, Tanith, Fletcher and Ghastly are hunting down Skulduggery's original skull. Valkyrie manages to do this, first tracking down a broker who happened to have the skull. The broker was contacted by a vampire called Caelan, but the skull turn out to be a fake. The broker reveals that he sold the real skull to the sanctuaries new detective, Davina Marr. Valkyrie, Fletcher, Tanith and Ghastly try to steal the skull fom Guild's office but they get arrested. Valkyrie and Fletcher escape, and together with China Sorrows open the portal to the Faceless ones. Valkyrie says that she will go through alone. Neither China nor Fletcher like the idea and Fletcher unexpectedly kisses her before she goes through. She arrives in a deserted city, surrounded by a desolate landscape. She finds a gibbering Skulduggery in a cave, who thinks Valkyrie is nothing but a hallucination. He reluctantly reveals that the Faceless Ones managed to escape the dimension that the Ancients sent them to, destroying countless innocent worlds before somehow getting trapped on the world that they currently inhabit with Skulduggery. They are attacked by a Faceless One and a variety of strange creatures that seem to serve the Faceless ones. After an extended battle with these, China arrives through the portal which finally convinces Skulduggery that he is not hallucinating as he mentioned that he never sees two people in his hallucinations.

Vaurien Scapegrace, Dusk, Springheeled Jack, Remus Crux, Billy-Ray Sanguine and his father, Dreylan Scarab, are plotting to destroy the Sanctuary. Dreylan Scarab had been locked in prison for 200 years for a crime Thurid Guild framed him for.

After hearing about the fact that seniives have been having visions, Skulduggery takes Valkyrie to Finbar Wrong, who takes them to a fellow sensitive - identified only as Cassandra. Valkyrie is shown the future where she is around nineteen and the world is crumbling around her and a new and terrifying villain named Darquesse inflicts destruction upon the world and kills Valkyrie's parents. Valkyrie decides to combine her powers of elemental magic with her newly being learnt powers of necromancy, which she has been learning from Solomon Wreath. Upon arriving home, Mrs Edgely, Stephanie's mother, reveals she is pregnant.

Skulduggery then visits Kenspeckle Grouse, but he is kidnapped by Billy-Ray and Springheeled Jack. Jack also manages to kidnap Tanith. Skulduggery asks for help from the vampire Caelan and he takes them to the vampire headquarters, where Valkyrie is almost killed by Infected. However, she manages to discover the Revengers are using a castle as a hideout and they have taken a soul catcher, in a plan to possess Kenspeckle with an evil demon, and force him to repair their bomb. The team heads to the Midnight Hotel, where the creatures are being kept and meet the owner Anton Shudder. Before Skulduggery can check on them, they are attacked by Zombies, led by Scapegrace who has been turned into a zombie by Scarab, and in the confusion Billy-Ray manages to capture a creature.

The group decides to investigate Nefarian Serpines old castle and Valkyrie discovers a hidden door through which the possessed Kenspeckle has been repairing the bomb, as well as torturing Tanith. Valkyrie saves her and delivers the bomb to Marr, and they expel the demon from Kenspeckle, who then recalls as well as repairing the first bomb, creating a second.

The team track Scarab and the others to a stadium. A fight breaks out in which Dusk bites Valkyrie and knocks out Fletcher. Thurid finds Scarab and takes the bomb off him. Sacarb reveals that is Thurid drops the bomb it goes off, he won't be killed but everyone else (80,000+) in the stadium will die and that Billy-Ray has his family. Thurid leaves. In another fight, he drops the engine just after Fletcher teleports them away. Thinking they are both dead, Valkyrie goes after Billy-Ray. She saves Thurids family after Billy leaaves and apartently over his grudge. Back at the staduim, Marr, cleavers and other santuary workers take Sacarb and Springheeled Jack away. Fletcher and Thurid return and reveal that they teleported to the ocean. Thurid thanks Fletcher and the others (every time Fletchers says 'But mostly me'). Fletcher takes Valkyrie to Grouse, but before been treated, Valkyrie kisses him. When Valkyrie has recovered, Skulduggery takes her to escort Thurid to Jail. She reveals that Fletcher and herself are a couple but Skulduggery isn't surprised. As they escort Thurid, Marr sets off an engine. It destroys the Irish sanctuary and Thurid loses his legs.

At the end of the book, Valkyrie wakes from a nightmare. Using a dreamcatcher from Cassandra, it reveals Valkyrie's true name- Darquesse(The most evil sorceror who ever lived, and who was predicted to return to the Earth to destroy it and scourge the human race, along with the rest of it's inhabitants.