Rosemount was a small town like Gracepoint where both Renee Clemons and Emmett Carver used to work. Carver had worked there on a case which can be assumed to be relatively similar to the Gracepoint one, as Carver says the fact he took that case meant he was the right person for the Danny Solano case. Renee had followed that previous investigation while working at the newspaper in Rosemount, and it was because of this that she became interested in the Gracepoint murder, especially once she knew Carver was involved again. (Episode 1)

The case at Rosemount involved the disappearance of three young girls; Nina, Sydney, and Megan. Apparently, Carver fumbled the investigation somehow, and then disappeared himself after the case. (Episode 2)