Steph Broadribb
Lori Anderson, a single mother working as a bounty hunter, in Florida:

Deep Down Dead (2016)
Finalist 2018 Thriller Award for Best First Novel

Deep Blue Trouble (2017)

Deep Dirty Truth (2018) [US due January 5, 2019]

Written as Stephanie Marland
Clementine Starke, member of an online true-crime group, working with detective inspector Dominic Bell, in London, England:

My Little Eye (2017) [US due January 15, 2019]

You Die Next (due April 4, 2019)