Over the next half an hour, they were faced with numerous forks in the tunnels and nearly as many dead ends. This disheartened Marty, as he began to resign himself to the fact they would never make it to the mouth of the cave, which would be the most likely location for the merfolk to reside.

Now they were floating in proper trim in a passage about three meters wide and five high. Ahead of them it shrank into yet another restriction…from which he could feel a slight current. This buoyed his spirits, as he believed the current meant it likely connected back to the main conduit from which they had deviated at some point. Even so, proceeding would be chancy. The two previous restrictions would be classified as “minor” in diving terminology. This one would be classified as “major,” meaning they would need to unbuckle their tanks to get through.

Marty checked his dive computer: they had ten minutes before they had to turn back.

Was the major restriction worth exploring given how little time they had left and the high risk involved? Or should they play it safe, cut their losses, and call it a day?

Marty knew the answer right away, but he wasn’t going to endanger Elsa again.

He signaled for her to wait where she was, then removed his tanks from his back. She tapped him on the shoulder and shook her head. He thought she was telling him not to proceed, but then she signed that she was coming with him.

There was no time to debate the matter, or even a way to do so, and he simply nodded.

Pushing his tanks ahead of him, he entered the shaft first.

∆∆∆

He had to swim sideways to fit through the tight space. After a short distance the passage doglegged. He twisted his body to swim upward, his tanks scraping the rock the entire way. Thankfully there was little silt due to the current, and his visibility remained good. Then the tunnel leveled out again, but it was so shallow that even with perfect buoyancy he was dragging his belly on the ground and hitting his head on the ceiling at the same time. There wasn’t room to look behind him to see how Elsa was doing.

He tried not to think about what they would do if the squeeze tightened to a point that they couldn’t pass through.

And then it did just that.

He hesitated a moment, then shoved his tanks through the basalt sphincter. They became wedged.

Cursing to himself, he shoved again.

They popped through.

Marty exhaled to make his chest smaller, sucked in his belly, and bullied his way through too.

∆∆∆