The spider's web: She finds an innocuous corner in which to spin her web. The longer the web takes, the more fabulous its construction. She has no need to chase. She sits quietly, her patience a consummate force; she waits for her prey to come to her on their own, and then she ensnares them, injects them with venom, rendering them unable to escape. --- Donna Hope

John and Sherlock have something in common of which they are both unaware. They've both been holding back from starting a relationship with the other because of the one aspect of their lives they are *sure* they cannot share. Serial Killer AU.