Free The Gods of Atlantis by David Gibbons

It was no illusion; he really had been falling. He began pulling himself along, his buoyancy computer continuously adjusting to compensate for the effect of being dragged down in the vacuum created by the bubbles. He reached the grapple, checked that it was locked securely into a crack and then turned to look for Costas, who had crouched down on the edge of the tunnel opening, holding the line. Jack held on to the rock face with one hand and put his other out in the diver’s okay signal, his forefinger and thumb joined in a circle, and then transferred both hands to the line. He heard Costas’ voice crackling on the intercom through some kind of interference, the broken sounds briefly becoming distinct. ‘You ready?’
    Jack wedged his body as much as he could into the rock. ‘Roger that.’
    Costas launched himself forward in a slow-motion dive, his bulky suit making him look like an astronaut. As the line went slack, Jack hauled on it, looping it quickly around a rock protrusion behind him. It suddenly went taut as Costas was sucked down by a gas plume and disappeared out of sight. The line went slack again, and for a horrible few seconds as he frantically pulled on it Jack thought that Costas might have impacted with the lava. Then the crackling came on the intercom again, and Costas appeared out of the plume and ascended a few metres below him. He reached the ledge beside Jack, then wedged in an elbow and took the grapple gun out again from his pocket, unhooking the line from the carabiner on his chest and feeding it back into the tube. He glanced at Jack through his visor. ‘That was close.’
    ‘Your boiler suit looks like glue.’
    Costas grunted, reached into the crevice to disengage the line from the grapple, then pressed a control on the tube to re-spool the line and hook it back into the second grapple, ready for firing. He wrapped his hand round the grip again and peered at their objective, the rock-cut platform in front of the ancient entranceway some fifteen metres away. ‘Twice lucky?’
    ‘Go for it.’
    There was a jolt as he fired the device again, and Jack watched the grapple arc over and disappear into a fold in the rock about a metrebelow the ledge. Costas pulled hard, and the line went rigid. He leaned back and Jack swam over him, taking the line in one hand and kicking out above it. This time he quickly made it to the opposite side and Costas followed, swimming forward while Jack hauled, not bothering to loop the line but letting it drop down below. Costas reached the rock beside him and hung on, breathing heavily on his regulator, then he grasped the line near the grapple and let go of the rock to release the carabiner. As he did so, Jack saw a white expanse of gas billow up below them, and at the same moment the rock holding the grapple broke free under the tension and tumbled off the face, dropping down below Costas into the fomenting mass of bubbles now rising up around them. Jack wedged one hand into the rock and reached down with his other to grab Costas under one arm, holding tight as the plume rose through them. For a split second it seemed as if they were dangling in air, and Jack was holding Costas’ entire weight. Then the plume dispersed above them and Costas hit the manual on his buoyancy control. Jack twisted round and looked up, seeing the carved lintel shape above the doorway, straining to look for the ancient symbols he desperately wanted to see.
    Just as he relaxed his hold, there was a jerk and Costas’ arm slipped away. Jack twisted back and saw a horrifying sight. Costas was at least five metres below him, his arms flailing, descending fast. Jack slammed his buoyancy control to dump the air inside his compensator and swam downwards. The chunk of rock with the grapple still inside had pulled Costas down like an anchor, and was now embedded in the lava near the edge of the chamber, sinking in and pulling Costas with it. Jack reached him with only a few metres to spare,