Death in Small Doses

Nancy Lyon is rushed to the hospital, where she dies from arsenic poisoning. Detectives Ortega and A.D.A. Sims begin a formal investigation into her death, collecting interviews and clues in Dallas, Texas.

The Dillards tell investigators that Nancy and Richard had recently reconciled after Richard left to be with his mistress. Nancy had suspected Richard might be poisoning her, but she did not involve the police. The interview sets up potential motives tied to wealth and marital strain.

Nancy's brother Bill accuses Richard of killing Nancy to inherit her fortune. He argues that Richard had motive to remove Nancy and control the family's wealth.

Ellen the nanny testifies that Richard was a loving father to the couple's two children. Her testimony adds complexity to the case by contrasting with mounting suspicions about his actions.

Flashbacks reveal Nancy and Richard's marriage: both were architects, but Nancy's greater success kept her away from home. Their professional ambitions strained their relationship and sparked frequent arguments about Nancy's family.

The police discover that Richard had recently purchased arsenic, which he claims was for a fire ant problem. He suggests his lawyer Guthrie review whether Nancy could have committed suicide. This broadens the scope of possible motives.

During a family trip to Arizona, Nancy visits Bill at a treatment center. After the trip, she isolates herself, quits her job, and begins seeing a therapist, while Richard begins an affair and files for divorce. He later returns to Nancy for the sake of their children.

Anonymous letters arrive claiming Bill is responsible for Nancy's poisoning. The sender remains unidentified, and Richard remains the police's prime suspect.

A grand jury indicts Richard, and he is arrested. He is placed on trial for Nancy's murder, setting the stage for courtroom confrontations.

During the trial, Guthrie accuses the police of overlooking Bill as a suspect. The defense cites other leads to cast doubt on Richard's guilt.

Therapy sessions reveal a shocking detail: Nancy and Bill had an incestuous past during childhood. The notes also mention Nancy's fears that Bill might have sexual desires toward her daughters. These revelations complicate the case and affect the jury's perceptions.

Testimony introduces an arsenic invoice with Nancy's signature and questions its authenticity. A plant owner testifies that a woman inquired about arsenic but did not purchase any. A handwriting expert also attests that the notes show both Nancy and Richard's handwriting, suggesting the evidence may have been doctored.

Bill agrees to a polygraph test, but the result is inconclusive. The unresolved test adds to the tension in the courtroom and keeps the focus on Richard's guilt.

The jury finds Richard guilty of first-degree murder and he is sentenced to life imprisonment. The verdict concludes the case and leaves the family to grapple with the tragedy.