Henry Gordon Jago was the owner of the Palace Theatre in London, where Li H'sen Chang performed his magic act. He and Professor Litefoot aided the Doctor and Leela in defeating Magnus Greel. (DW: The Talons of Weng-Chiang)
His association with Professor Litefoot is known to have continued beyond their adventure with the Doctor. The pair were involved as amateur sleuths in at least one other mystery. (BFA:The Mahogany Murders)