I really shouldn't be doing a one-shot , not with everything else that I need to do! But I just finished the Mark Of Athena, and…well you'll see. Sherolly. Some of this will be Rick Riordan's, some will be mine. And of course, all characters belong to BBC and ACD. It's here because the reader pool in the crossovers was small, and well I thought you guys would like it more. Spoilers for the Mark of Athena.

In this Sherlock is a son of Poseidon, Molly a daughter of Athena, John is the son of Hades. That is all you need to know.

So without further ado- Allons-y!

John had just reached the ladder when a sharp pain shot up Molly's bad leg. She gasped and stumbled back, her feet sweeping out from under her. She cried out as she felt herself being dragged backwards. Sherlock lunged forward, and grabbed her flailing arm, but he was also pulled off his feet, and dragged along too. Molly could hear Sherlock shouting

"Cut her ankle! Cut it!"

Molly didn't understand, and anyway no one could hear him over the din of moving the statue. The only people who had noticed were John and Lestrade. But they were too far away to help.

Molly sobbed as she hit the edge of the pit. Her legs flew over the side. Too late she realised what was happening; the spider silk had tangled around her foot and it was attached to something heavy down in the darkness, and it was pulling her in.

"No!" Sherlock shouted "My sword!"

Molly realised that he couldn't reach his sword without letting go of Molly, and Molly knew he would never do that. She slipped over the edge and Sherlock fell with her.

A huge jolt shocked her body, almost dislocating her arm. Molly realised that she had fallen partway into the pit and was dangling over the void. Looking up, she saw Sherlock had managed to grab a ledge 15 feet below the top of the chasm. He was holding onto the tiny ledge with one hand, and Molly's hand with the other. But they both knew that that the pull on her leg was far too strong.

No escape said a voice from the darkness below I go to tarturus and you will come too

Molly wasn't sure if she had imagined it. The pit shook. Sherlock was the only thing keeping her from falling, but he was barely holding on himself. John was leaning over the edge, thrusting out his hand, but the was much too far away to help. Lestrade was yelling for the others, but if they even heard him, they would never make it in time.

Molly's leg felt like it was pulling free from her body. The force of the underworld tugged at her, and she didn't have the strength to fight. She knew she was too far down to be saved

"Sherlock, let me go" she croaked. "You can't pull me up."

His face was white with effort.

"Sherlock, please! Let me go!" Molly pleaded

She could see in his eyes that he knew it was hopeless.

"Never," he whipered.

He looked up at John, fifteen feet above.

"The other side, John! We'll see you there. Understand?"

John's eyes widened. "Sherlock no!"

"Lead them there!" Sherlock shouted. "Promise me!"

"I-I will."

Below them, the voice laughed in the darkness. Sacrifices. Beautiful sacrifices to wake the goddess.

Sherlock tightened his grip on Molly's wrist. His face was gaunt, his high cheekbones were like a skeletons. His face was scraped and bloody, his black curls dusted with cobwebs, but when he locked his magnificent muli-coloured eyes with her, she thought he had never looked more handsome.

"We're staying together," he promised. "I spent too long pushing you away. You're not getting away from me. Never again."

Only then did she understand what would happen. Falling's just like flying except there's a more permanent destination

"As long as we're together," she said.

She heard Sherlock turn and say to John

"Goodbye John"

She heard John scream Sherlock's name. She strained to see sunlight far, far above- maybe the last sunlight she would ever see.

Then Sherlock let go of his ledge, and together, holding hands, he and Molly plunged into the endless darkness, John's last anguished scream echoing in her ears

"SHERLOCK!"