Leda first appears in the fourth case A Barrell Of Corpses where she is the counter woman at a local pharmacy dealing the drug Maxamine which was rendered to Monaco Casino Victim Sophia Bennedetti. You first interrogate Leda at the pharmacy but after you and Warrick Brown confirm enough evidence involving the spiked tissue and flirtatious doctor Wilkinson she is brought in for questioning at the police station. From there she reveals she and Wilkinson like Sophia were getting it off hot and heavy until his controlling pompous wife found out.