Investigator Susan Goreck spent a year undercover, risking her life and even befriending a killer, to find out the truth behind the poisoning murder of a Florida mother.

In the spring of 1989, special agent Susan Goreck went undercover to investigate a potentially dangerous and ingenious man named George Trepal. Trepal was suspected of poisoning an entire family in his neighbourhood. At great risk to both herself and her family, Susan took on the alias, Sherry Guin, a young woman going through a messy divorce.

Sherry would be someone Trepal could protect and hopefully confide in. But would her efforts to get close to an alleged killer yield enough evidence for a conviction before he discovered her true identity? The pressure was on.

For a year, Susan befriended Trepal, built up his trust and even rented his house when he moved out of town. However, when Susan moved in, she brought the police with her.

It was in Trepal's garage that she finally found what she had spent a year trying to obtain: evidence potent enough for a death row conviction.