Trivia

The animatronic Phoenix used for close ups and head movement was a radio controlled model and built by the same in-house technicians who built K-9 for Doctor Who.

Despite it's crude visual effects and small sets this remained one of the most memorable children's television series of the 1970s. It received several repeats, usually during school holidays, for the rest of the decade but hasn't been shown since. In 1995 the novel was turned into a feature film and a more lavish TV adaptation was made by the BBC in 1997. In 2019 the BBC finally relented to the constant requests and accusations that the tapes had been wiped and released a basic original, unrestored 1976 version on DVD.

Puffin books re-released the paperback novel with a still from the TV show on the cover in the run-up to Christmas 1976. It subsequently became one of the best selling childrens books of 1977 despite having originally been published in 1904.

As depicted in the story there really was a Phoenix Assurance Company in London. It started in 1781 until 1984 when it was bought by Sun Alliance. Due to a series of mergers since then it re-emerged in 2010 as an umbrella organization called Phoenix Group Holdings. Due to the BBC's strict policy at the time this show was made, it is quite extraordinary that a real company was so blatantly name-checked in a children's TV show (although the fact that it is mentioned in the 1904 novel may have made a deviation from the original source difficult to avoid).

Filmed during the summer of 1976 in studios 'A' & 'C' at the relatively new BBC Birmingham studios in Pebble Mill. The Pebble Mill studios were closed in 2004, demolished in 2006 and the land redeveloped into a dental training school.