The Devil's Cave: A Bruno Courrèges Investigation (Bruno Chief of Police 5)

way to a small cave of smooth-walled limestone, too smooth and unbroken to have been made by man.
    He was in a kettle, a hollow formed over millennia by underground rivers. The gap he’d come through from the chapel was itself a watercourse. When heavy storms made the underground river surge, the swirling waters must have carved this small cave. He tried to imagine the power of that water, how it had honeycombed these hills and gouged out the caves that prehistoric people had made into showcases for their art. Further down he should find the course of the underground river that led to the Gouffre. Descending carefully, facing the steps, he was now at least a dozen metres below the chapel and the steps still led downward.
    He called Isabelle’s name, but no response came, the blackness ahead seeming to soak up every sound. At least now he could see some kind of floor when he took his torch from his mouth and shone it downwards. Whoever had come this way with goat’s head and paint must have used a rucksack, and must have known the route, too.
    The floor and walls of the tunnel were smooth but damp, almost as if he were in a giant pipeline. A small rivulet trickled down the centre. The tunnel was at least two metres high and the same in diameter. Its even floor was disturbed only by small stalagmites growing at irregular intervals, where water dripped from tiny fissures in the rock overhead. He called her name again, upstream and downstream, but got no response.
    On an impulse, he took Balzac from his chest and put him on the floor. Young as he was, the dog might pick up her scent. The puppy lapped busily at the tiny stream of water, looked around him and cocked his leg against the wall to leave his mark. Bruno shone the light upstream and with nose to the ground Balzac explored a little that way and then turned back past Bruno and began to lope downstream. Bruno followed, counting his paces to keep a rough sense of the distance he’d covered. He knew from the map that it was no more than a kilometre in a straight line between the Gouffre and the chapel. But this tunnel was turning in dog-leg angles, forced to change direction where the water had hit a harder patch of rock.
    At the count of three hundred and sixty, he heard the sound of running water, and after another twenty paces he saw a glow of light. He called out Isabelle’s name and with a surge of relief he heard a distant voice, distorted by echoes, but he was sure he caught the last long vowel of his name. He called her name in return and heard what he was sure was an answer.
    Although every instinct urged him on, Bruno kept his steady pace and his mental count. By four hundred and fifteen therewas a faint glow of light ahead. As he turned a final corner, Balzac darted ahead and they entered a large chamber that was lit by Isabelle’s torch, its light strengthened by its reflection from a large pool of still water that lay between him and Isabelle on the far side, perhaps twenty metres away. Balzac barked a greeting as Bruno’s torch illuminated her.
    ‘Are you all right?’ he called, his heart beating hard as the anxiety flooded out from his system.
    ‘I’m fine,’ she called back. ‘When I reached this pool I thought I’d wait for you. I don’t have a stick to probe it but it’s certainly deeper than my arm.’
    ‘There must be a way across,’ he called back. ‘How else would they have got to the Gouffre?’
    He took off his rucksack, shirt and jacket and plunged his arm in. The water was ice-cold but felt as if it were motionless; certainly he could feel neither bottom nor current. He stood up and flashed his torch to each side. The cavern was a large kettle, shaped like a dome. To his right the dome and the lake narrowed into what looked like another tunnel. Isabelle was perched on a thin beach of rock where her tunnel debouched into the cavern.
    He walked to the point where it narrowed but it was still too far to jump. There had to be some way across. The sound of running water was coming from within this cavern. Could there be another outflow? Even as the thought formed, he heard Isabelle calling something and looked across to see Balzac scampering towards her on the far side of the lake. How on earth …?
    Balzac had been coming from Isabelle’s right, so he walkedto his left and the sound of running water was louder. He lay down and put his arm into the lake, close to the cavern wall, and felt the water flowing over his arm. He