The Varrigal are demons encased in black armour and carry shieds, lances and swords. The Varrigal are most at home at night, when they can move undedected through the human world. The Varrigal had been summoned from Hell thanks to Obadiah Demurral and they form the main muscle of Hell's army.
The Varrigal first appear in the opening, where one of them chases Thomas down off the cliff of Baytown and sends him falling into the ocean, but he is saved by Raphah. Thomas and Raphah then go to break into the Vicarage because Demurral has stolen from Raphah, and Demurral sees the intruders so he threatens to send a Varrigal out after them. The Varrigal hunt them down through the wood and eventually Thomas and Kate meet Jacob Crane the pirate. Jacob gets summoned to Demurral where he shows him his dark magic and to be wary of Demurral. Later on Demurral sends the Varrigal out after Jacob when he is in the wood. The Varrigal light a Wicker Man to scare them and the horses run. Soon Thomas is reunited with Raphah and they lose track of the Varrigal for a time.
When Lord Finesterre "shelters" them at his mansion, Raphah, who was staying alert because he feared the worst, is notified by the pirates bombing Demurral's house, and then Raphah sees witches doing dark magic down in the garden. They summon forth an army of Varrigal from Hell itself. The witches are revealed to be Demurral, Captain Farrel, and none other than Lord Finesterre, shocking Kate and Thomas. Soon Demurral's master Pyratheon appears out of the ranks of the Varrigal and welcomes them all. Pyratheon sends the Varrigal after Thomas and Kate.
Later at the church, they are all ambushed by hordes of Glashan and Varrigal, the Varrigal protecting Pyratheon who appears in the church. The Varrigal fight against the invading pirates and attack Jacob Crane but the Varrigal vanish with Pyratheon when he flees from Raphael the Archangel.