Beyond the doors was a vast, circular chamber, like a great cylinder carved straight out of solid rock. Some twenty-five metres across and at least twice as high, it was enough to boggle Jason’s mind even through his punch-drunk haze. The walls were black, like some long-dormant magma chamber, but even starting from a natural cavern it would have been a monumental labour to bring it to its current state. Flat stone slabs, carved out of the same black stone, had been inserted into the walls like pegs. They made a punishingly steep set of stairs that wound their way up to the higher parts of the chamber.

Dominating the room was a red pool of roiling, bubbling liquid, taking up almost all the floor space. It was the source of the light, along with the heat and the coppery stench of blood. The centre of the pool churned, as if on the point of boiling. The sound of thick, sloshing liquid echoed up through the chamber. The red light shone from deep within the pool, washing the whole chamber in red as if everything was coated in blood.

“That isn’t good,” Jason heard from one of the other caged people. It was Rufus, who had told him how to use the spirit coins. The lion man was there in his own big cage, along with one of the two women. The other was nowhere to be seen. One of the robed cultists bashed on the side of Rufus’s cage.

“I said quiet.”

“Or what?” the lion man grumbled. “You’ll sacrifice us in your creepy ritual pit?”

The other prisoners were also dirty and ragged, but nothing like Jason. He had no shirt, no hair, and there was blood and old healing ointment crusted all over him. His face was coated in blood from his broken nose, along with puffy black eyes and flecks of vomit.

The rail that had carried the cages on platforms through the tunnel ended at the door. The cultists lifted the cages off, two people to each small cage, and four to the large ones. They carried them up the steep stairs, audibly straining at the effort. The lion-man’s cage was the most troublesome, even with four people lugging it. The stairs wound up and around the circular wall, the group pausing after a quarter turn. They had reached a platform, set into the wall like the stairs, but much larger. It extended well over the blood pit below.

“Leave the big one first,” one of the cultists said. “No point carrying the heaviest one all the way to the top.”

Jason recognised the voice of the woman he had heard in the cellar while pretending to be unconscious.

“Thank you, milady,” one of the cultists said gratefully. Jason recognised the voice as the shovel-carrying man she had addressed as Dougall.