When a customer of William Doughtys chemist shop dies of strychnine poisoning after drinking medicine he dispensed William is blamed & the family faces ruin. Williams daughter nineteen year old Frances determines to redeem her ailing fathers reputation & save the business. She soon becomes convinced that the death was murder but unable to convince the police she turns detective. Armed only with her wits courage & determination & aided by some unconventional new friends Frances uncovers a startling deception & solves a ten year old murder. There will be more deaths & a secret in her own family will be revealed before the killer is unmasked & Frances will find that her life has changed forever.