This is a Perry Mason TV episode in which the character Perry Mason does not appear.
    In the case of the Lethal Lifestyle a TV Talk Show host - Adrian Lye - is murdered whilst attending a showbiz opening of a luxury Hotel. Many of the people scheduled to appear on his show are 'star guests' at the event.
When it is discovered that he has been blackmailing his 'guests' they are the prime suspects in the murder case.
    In particular one man, chess Grand Master Daniel Kingman was seen arguing with the victim, and he was also said to be the last person to have seen him alive. The case against him is strengthened when it is realised that the victim was poisoned by an overdose of a medicine used to treat asthma, and the accused suffers from asthma.
He is arrested and put on trial, his defence is conducted by William McKenzie (Hal Holbrook) an old friend of Perry Mason.
    During the trial a surprise witness comes forward, Dr Estes (Derek de Lint) the Doctor testifies that he administered the drug to the defendant to treat him for an asthma attach and he also gave him a prescription for further treatment. Thereby establishing that Kingman had access to the drug that killed Lye..
However in the telling moment of the trial the Dr. Estes is challenged to once again administer the drug to the efferent, he does this and Kingman immediately goes into severe shock. The Dr. must quickly administer an antidote to save him. This reaction established that in fact Kingman is allergic to this particular drug and therefore it is obvious that Dr. Estes must have been lying about treating him with it earlier.
    As happens in most Perry Mason episodes in the final moments one of the other guests, and a victim of Lye's blackmail - Mrs. Louise Archer (Dixie Carter) is called as a witness. It transpires that she and Dr Estes are lovers who have been conspiring to keep her husband confined to a hospital run by Dr Estes whilst she make use of the husbands wealth and position.
Louise Archer confesses that she hired a killer to get rid of Adrian Lye and Daniel Kingman is freed, justice triumphs!