What is the plot of the movie above suspicion

Above Suspicion is a 2019 American crime thriller film directed by Phillip Noyce, from a screenplay by Chris Gerolmo, based upon Joe Sharkey's non-fiction book of the same name revolving around the murder of Susan Smith. It stars Emilia Clarke, Jack Huston, Sophie Lowe, Austin Hébert, Karl Glusman, Chris Mulkey, Omar Miller, Kevin Dunn, Thora Birch and Johnny Knoxville.

It was released in the United States on May 7, 2021, by Lionsgate.

An ambitious rookie agent is assigned to an FBI field office in the run-down town of Pikeville, Kentucky. The married man recruits a local drug-addicted woman as his informant and gets involved with her, thereby setting in motion a downward spiral of jealousy, betrayal and violence.