Did you know that the original, 1937 version of A Star Is Born may well have been based on a true story, first aired in an earlier, 1932 movie called What Price Hollywood? Yet every word of dialogue in the original Star Is Born was invented, all of its characters fictional, all of its scenes made up.

By the time of the 1954 remake, the female lead had gone from being an aspiring actress to an aspiring singer, played by Judy Garland, looking for her big break. Her mentor is still the addictive personality of the original film but this time he’s a has-been singer, not an actor, and crucially he doesn’t commit suicide before the film’s end (apologies for the spoiler.) Practically everything about this remake – its dialogue, characters, songs (songs? Where’d they come from?) settings and scenes – is different and, once again, is completely made up.

In the Barbra Streisand 1976 version, the female lead is once again a singer, her mentor a rock star whose career is on the slide. This film is about the perils of a rock’n’roll lifestyle and the passionate relationship between the two protagonists. It bears only the scantest relationship to its predecessors, never mind the original true-story that inspired the first film. Again, everything in it is pure invention.

Which brings us to the fourth version, starring Lady Gaga, that borrows a little something from all of the previous films. All the same, it alters the story, creating completely new scenarios, dialogue, songs and settings. It would be unrecognisable to the original audience of the first A Star Is Born, as different from that film as… well, as John’s gospel from Mark’s.

As the various versions of the film demonstrate, stories evolve. They are fluid and in their telling and retelling they change. Their creators adapt them and ‘improve’ them to meet the evolving tastes of their intended audience. They happily invent new episodes, new scenarios and new dialogue.

And so it is with the gospels: Mark’s original based on the visions of a few people from 40 or so years earlier; Matthew and Luke’s based on Mark’s – with their own largely invented additions – and John’s (the Lady Gaga of the set) a wild reimagining of all three. Apart from the outline of the story (which they get from Mark), every one freely adapts everything else: dialogue, scenarios, pericopes and, yes, songs.

We’ll look in detail next time at the evidence, still apparent in today’s versions of the gospels, at how we know this to be the case.