This con, originating in 1897, is an early iteration of the Nigerian email scam. In the Spanish Prisoner scheme, victims receive a letter (postmarked from Barcelona) from an imprisoned individual who writes:
I beseech you to help recover" a large sum of money "my portmanteau containing a secret pocket... As compensation I will give up to you the third part of the sum, viz, £25,000.
The letter goes on to say,
I cannot receive your answer in the prison, but in case you accept my offer you can send a telegram to a person of my confidence...
Cultured, charming and dangerous, Andrew George Scott (c.1842–1880), known as ‘Captain Moonlite’, was an Irish-born bushranger. Awaiting execution at Darlinghurst Gaol in 1880, he wrote many letters which were never sent by authorities and are now preserved in the State Archives Collection