Sherlock Holmes in the 22nd Century (1999)

S01E10 The Sign of Four

Mary Morstan approaches Holmes with a troubling mystery. Unraveling this enigma will take them all the way to the moon! Years earlier, her father lost his life in a mining accident there, and Mary is discovering that the events surrounding his death were peculiar at the time. Now, as she delves deeper, she realizes the aftermath is even more bizarre.