In 2000, David Calcutt (www.davidcalcutt.co.uk) wrote a very interesting play which is quite faithful to the original Beowulf story. It was published by Nelson Thornes in 2001.
When I read the play, I noticed that he made a few changes. He had Beowulf cut off Grendel's mother's head with Unferth's sword Hrunting, rather than with Grendel's mother's giant sword (he leaves out the giant sword altogether). He also leaves out the part in which Beowulf finds Grendel in the cave, and cuts off Grendel's head. I also noticed that he changes the fight with the dragon a bit, and has Wiglaf jump in to fight the dragon after Beowulf has already been disabled, and Wiglaf stabs and kills the dragon while Beowulf is lying off to the side. I wrote to David Calcutt to ask about these changes. Here is part of his response:
Usually, the changes I make when making any adaptation are to do mainly with considerations of theatre and performance - I have to create a piece that will work in the theatre, and will work simply and dramatically. When creating the Grendel's cave scene, I wanted the drama of the scene to focus on the meeting between Grendel's Mother and Beowulf, and, most importantly, on what she had to say about the relationship between humans and monsters. It wasn't the fight that was important, as it had been in the case of the fight with Grendel. I felt that having to "explain" the melting of Beowulf's sword, and the finding of a second would have detracted from the drama. Similarly, the cutting off of Grendel's head would also have proved a similar kind of detraction. Generally, while the epic poem form can afford to be leisurely, a play has only a limited time in which both to tell its story and to make its dramatic points, so cuts and alterations do have to be made. Because of these constrictions, once I've digested the work I'm going to adapt, I try to put the original work out of mind, and imagine I'm creating the play from scratch, so to speak, writing the story for the first time in dramatic form. I'm sure you've noticed, for example, that I erased the Christian gloss the writer placed on what must have been, originally, a pretty stark, pagan Norse tale. I tried to get back to this original in my play, hence the use of the Norns as narrators, and controllers of fate.
I've always been a great admirer of "Beowulf", ever since I first came across a children's version of it when I was a boy, and hope I've at least gone some way to doing it justice.
I certainly think that he has done this story justice, and I hope that I can see a performance of it some day.