Six miles below the surface of the ocean, Mia has to solve a locked-room murder mystery before the crime scene is completely flooded.

This supernatural mystery set in the world of Sherlock Holmes and Lovecraft's Cthulhu Mythos features a brilliant detective and his partner as they try to solve a horrific murder. The complex investigation takes the Baker Street investigators from the slums of Whitechapel all the way to the Queen's Palace as they attempt to find the answers to this bizarre murder of cosmic horror.

The remaining survivors of Dept. H abandon the deep-sea base and prepare for their long-awaited ascent. But life above the waterline remains uncertain for the team, and the pressure to solve Hari's murder continues to strengthen its grip on Mia. Secrets and memories begin to surface, but before Mia can unpack the mystery, she must decide the fate of those still stuck six miles below sea level. As the water rises, Mia's time runs out.

The next entry in the meta-fictional D&D adventure series based on the McElroy family's podcast finds the heroes on a railroad murder mystery involving a genius child detective and an axe-wielding pro wrestler.