Guilt and Innocence

The investigation revolves around determining who is guilty, but the characters' own admissions—like Mrs. Endicott's confession of intent to kill—complicate the notion of innocence, and the police themselves are unsure whether the true criminal is still at large.

Valcour's investigation into who caused Endicott's shock and Roberts's suspicious behavior point to questions of guilt and hidden knowledge.

Hollander's denial of guilt and Valcour's attempts to establish his culpability, while also considering Mrs. Endicott's potential involvement.

Valcour's questioning of Vickers and Roberts explores who might be guilty, with Roberts's hysterical behavior suggesting possible guilt or trauma.

Roberts's contradictory statements and her admission of hiding a gun raise questions about her guilt and innocence.