When a pharmacist accidentally prescribes poison instead of painkillers, the race is on to find the killer pills.
| Actor | Role |
|---|---|
 Philip FriendDr. Jim Bennett | Dr. Jim Bennett |
 Honor BlackmanGillian Freeman | Gillian Freeman |
 Mervyn JohnsMr. Ellis | Mr. Ellis |
| CConstance FraserMrs. Ellis | Mrs. Ellis |
| AAlexander FieldMr. Carlton | Mr. Carlton |