Which 1982 British television series, produced by Granada Television, explores the formative years of the famous detective, portraying him as a brilliant and curious 17-year-old schoolboy solving mysteries before he met Watson?

The 1982 British television series that delves into the early life of the famed detective before his partnership with Dr. Watson is titled Young Sherlock (Review): The Mystery of the Manor House. Produced by Granada Television, a company that would later become synonymous with Sherlock Holmes adaptations, this eight-episode series first premiered on October 31, 1982. It offered viewers a unique glimpse into the formative years of a brilliant yet curious 17-year-old Sherlock, long before he became the iconic resident of Baker Street.

In this particular incarnation, actor Guy Henry took on the role of the youthful Sherlock Holmes. The series presented a storyline where a young Holmes, returning home from school due to a typhoid outbreak, found himself embroiled in a mystery surrounding his family's manor house. He had to employ his nascent deductive skills to uncover the sinister secrets of the new occupants, leading him to a plot involving a priceless diamond and a conspiracy to assassinate Queen Victoria.

Young Sherlock: The Mystery of the Manor House was an early attempt to explore the detective's origins, predating other well-known interpretations of his youth. While there was no direct televised sequel, the series' writer, Gerald Frow, penned a follow-up novel titled Young Sherlock: The Adventure at Ferryman's Creek in 1984, continuing the adventures of the young sleuth. This production by Granada Television holds a notable place in the canon of Sherlock Holmes adaptations, showcasing a period in his life when his extraordinary talents were just beginning to blossom.