It stars Barnaby Kay and Jana Carpenter (Simpson's spouse) as the two podcasters, Matt Heawood and Kennedy Fisher, with Nicola Walker as Eleanor Peck, a specialist in myths and the occult who helps their investigations.

Each season of The Lovecraft Investigations is titled after, and mostly based on, one of Lovecraft's works, namely 1927's The Case of Charles Dexter Ward, 1930's The Whisperer in Darkness, 1931's The Shadow over Innsmouth, and 1936's The Haunter of the Dark while creating an overarching story; it is also set within Simpson's Pleasant Green Universe of audio dramas, with the character of Fisher notably appearing in Simpson's Who is Aldrich Kemp?

In The Whisperer in Darkness, the duo investigates Henry Akeley, an elderly man from Suffolk and former acquaintance of Eleanor Peck, a woman who helped them in the case of Charles Dexter Ward.

Although Akeley contacted Peck claiming to have important things to share, upon arriving to his house, he is nowhere to be seen, and the clues and recordings he left behind are puzzling.

[4] Karen Rose produced all three of the initial series, with sound design by David Thomas and music by Tim Elsenburg.