Merlin's creators are hoping to attract a family audience
When you think of Merlin, instantly the image of a man with a long white beard, pointy hat and a gnarly staff helping a great king springs to mind.
But where does this very distinct, vivid image come from?
It's certainly very different from the Merlin depicted in the new BBC drama series beginning on Saturday, which will tell a family-friendly story of the wizard in his formative years.
But the "reality" of the character through the ages is actually quite diverse.
In the TV documentary Merlin - The Legend, which also screens on the BBC on Saturday, historians and experts discuss his origins, his influence through the ages and his supposed Welsh links.
It was the little-known clergyman Geoffrey of Monmouth who first wrote about Merlin in the 12th century in his book The History of the Kings of Briton.
According to Dr Juliette Wood from Cardiff university, the Merlin who appeared in his writing was not a real person, but a figment of Geoffrey of Monmouth's imagination.
MERLIN ON FILM
Excalibur (1981) Directed by John Boorman, this account of the Arthurian legend starred Nicol Williamson as Merlin
Monty Python and the Holy Grail(1975) The Monty Python take on the King Arthur legends, starring John Cleese as an explosion-happy Tim the enchanter
The Sword in the Stone (1963) Disney does Merlin with Karl Swenson providing the voice for the bearded one
King Arthur (2004) Stephen Dillane is Merlin in a demystified take on the knights of the round table
A Connecticut Yankee in King Arthur's Court (1949) Strangely, a singing mechanic from 1912 finds himself in Camelot, with Murvyn Vye as a villainous Merlin
"Geoffrey's purpose was to create a myth for the new Anglo-Norman aristocracy because they had left France and they had to justify who they were and why they were conquering this new country," she tells Merlin - The Legend.
"In order to do this he draws on Welsh tradition and he creates this powerful magician figure who becomes the person who organises the birth of Arthur and looks after King Arthur.
"Merlin is a fusion of two characters. One is wonder child Ambrosius, the other is the bard Merddyn Wilt and Geoffrey simply says that there was a character called Merlinus Ambrosius and suddenly we have Merlin."
According to Dr Wood, Geoffrey not only connected Merlin with the origins of the country in his book but also with Stonehenge telling stories which manipulated his audience into believing he had magical powers without ever stating categorically that he did.
Merlin is also a re-appearing figure in the famous Black Book of Carmarthen, which was written 750 years ago.
Maredudd ap Huw from the National Library of Wales said that here he was depicted as a very sorry, tragic character.
"He has obviously had some bad experiences in a battle," he explained. "He has become a figure who is living wild outside the boundaries of society.
"And from the hardship that he had suffered out came this wisdom that was respected by other people and held in high esteem."
In other medieval texts, it seems Merlin's character becomes more established and art historian Peter Lord says the reappearing character of an old, bearded man in a long gown makes him seem like a "medieval hoody".
Stories about Merlin have been linked to the creation of Stonehenge
Geoffrey of Monmouth has it of course that Carmarthen was the birthplace of the wizard.
He supposedly lived in a cave on the hill overlooking the town and it is also thought the cave is his tomb.
A festival celebrating Carmarthen's links with Arthurian legend has been running in the town since 2004 and people from all over the world make pilgrimages to the town.
During the time of the Tudors, it is thought the character of Merlin and King Arthur were used to bring stability to the country after the wars of the Roses. This is demonstrated in Thomas Malory's epic Le Morte D'Arthur.
Here Merlin is depicted as an advisor to his king and a stabilising influence from the old world in the tumultuous modern times.
In the 17th and 18th Centuries, a growing interest in ancient Britain led to Merlin being depicted as a druid and bardic figure in both literature and art.
And in the 19th Century, as the world went industrial, Merlin was depicted more as a romantic figure. He is overwhelmed by the seductive wiles of a woman in stories and art.
"It is perfect for the 19th Century because of the strong gender polarities," said Dr Wood.
He was half-human, born of a mortal woman and an incubus, or evil spirit, from whom he inherits his natural powers
He engineers Arthur's birth by enabling Uther Pendragon to enter into Tintagel in Cornwall in disguise and father Arthur with his enemy's wife Igraine
He created Stonehenge as a great memorial for a general in Ireland before transporting the whole thing to Salisbury Plain
His downfall came when lusting after a woman called Nimue, who coaxed out his magical secrets before using them against him to imprison him in a cave of glass
"Here is masculine, patriarchal Merlin with all of its own certainties giving way to this very, very seductive, very attractive but slightly dangerous power of femininity."
Even Nazi Germany is said to have seized on Merlin's powerful image to create their own myths and national identity.
The head of the SS, Heinrich Himmler is believed to have seen himself as a Merlin type figure who would advise the king - Hitler.
Their seizing of the Arthurian legends led to friends and fantasy authors JRR Tolkien and CS Lewis drawing on the complex Merlin associations to wage a literary war on the Nazis.
But what about now? What relevance does the bearded 12th Century wizard have on our technology-obsessed, disconnected and alienated society?
According to Dr Wood, his influence is alive and well in everything from Harry Potter to new age spiritualism.
"You can find him in Dumbledore and in Harry Potter himself. Through him children can do what they have always wanted to do which is become magicians themselves," she said.
"People now are very interested in somehow getting into a spiritual nature and Merlin has really become a Shaman.
"This is something that reflects the earliest Merlin, who was taken over by this kind of poetical ecstasy."
Whatever you take from the tales and depictions of Merlin, he has certainly been a powerful and influential character since he was created around 800 years ago. If only he was real...
Watch the latest dramatised version of Merlin on Saturday on BBC1 at 1930 BST. Merlin - The Legend will be screened on the same night on BBC2 Wales at 2015 BST.