"Serial" type shows were a staple component of kids TV here in the UK from the 70s through to the late 90s, CBBC producing loads, many based on semi popular childrens books and many original productions.
Said serials would usually feature children being the "hero" in some fashion, and would often take place in some sort of fantasy/sci-fi setting.
Although a popular format for over 30 years, its popularity waned in the late 90s and such types of show are now almost totally unheard of.
"Watt on Earth" had 2 series, each consisting of 12 episodes, both written by the veteran TV writing team of Pip and Jane Baker, and centred mainly around the misadventures of an alien prince, the titular "Watt" (geddit? "what/Watt" on Earth...puntastic!) and his human friend Sean, whose job it is to keep Watt hidden from his family (all of whom are journalists of some description) and generally keep him out of trouble.
Watt, who is considered a child on his home planet, despite being over 300 years old in Earth years, is the last remaining member of the royal family, his parents having been "killed in an accident" arranged by his evil uncle who has designs on crowning himself king as he has grown a bit sick of merely being the planets "regent protector", unfortunately for his evil plans, Watt, being the remaining heir, will become king when he comes of age.
Watt is sent into exile on Earth by a faction within his planets government who are still loyal to the royal family until such time as they can remove the Uncle from power and restore Watt to his rightful place as ruler. The uncle though, who isn't stupid, catches on to this plot and dispatches his faithful right hand man, Jemedah, to Earth to hunt down and kill Watt......(wow, heavy stuff for a kids TV show from the early 90s eh?).
Watts people are energy beings, so in order to blend in, Watt and Jemedah use a technique called "Transanimateobjectification" to appear as numerous people and objects found on Earth, although Watt, being only a child, isn't able to use this ability properly, so whenever he changes himself, he often messes it up, for example, in the first series, his human disguise (A shell suit wearing man in his early 20s) is ok apart from his ears being backwards, and in the second series, he gets his ears on the correct way, but they are green. He makes similar mistakes when he tries to imitate inanimate objects as well, such as becoming a teapot that has 2 spouts, an apple what has a blue flashing stalk etc.
The series itself is a fairly bland, middle of the road bit of TV filler, and is packed with teenage cliches, such as Seans sister being obsessed with pop music, and some inoffensive humour, most of which is derived from Watts inability to understand human customs and situations. One such "comedy sequence" that jumps out is during episode 3 where a whole 5 minutes is spent with Watt hunting around the kitchen looking for food, and ending with him making a cat food and squirty cream sandwich, which he then finds disgusting, but still eats anyway (Watt must keep his energy up otherwise he isn't able to transanimateobjectify, therefore he spends a lot of time moaning about being hungry).
The first series deals mainly with Watt acclimatising to living on Earth, but also trying to find out what is happening back home, the second series deals with Watt returning to Earth after being away for a fortnight, although due to relativity issues, a year has passed on Earth. The second series ends with Watt returning home for good to take his place as king.
Like i said, this series isnt too bad, although it is unashamedly a bit of filler used to pad out the CBBC winter schedules schedules between 5:10pm and when Neighbours came on at 5:25pm, its hardly memorable though when put alongside other childrens serials of the same type (in many ways, the show resembles CITVs sci-fi sitcom "Mike & Angelo", another series about an oddball alien arriving on Earth and befriending a series of young children. A show which incidentally ran for 11 years, I dont know why because it was a bit tedious).
As is the norm for CBBC serials, it has never been released on video/DVD, although a book was available, so if you want to watch this series, youll have to head over to Youtube, where several people have uploaded the series in fairly high quality video.