A man is shot outside of a party where cocaine is being used, & young Sheila Grant, the daughter of a retired general, may be implicated. Hercule Poirot receives a frantic phone call from Sheila's doctor, who says that she's an innocent bystander under the spell of a drug dealer Tony Hawker. After assuring the doctor that he will see that Hawker is dealt with, Poirot proceeds to go after the real culprit. Also included: "The Lernean Hydra"