About characters, Hrothgar is supposed to be a respectful king with his famous achievement in his journey to become the king of the Danes but in the movie, his appearance is a naked body with a long piece of silk and a crown in the head.
However, he is a social king and this thing makes the feast at the beginning of movie become a happy scene with joke, singing, drink, etc Grendel, a lustful demon, causes a very violent and bloody attacks in the Herot but Grendel appears as a poor demon in the movie.
One explanation is that they wrote it this way to leave the image of Grendel to the imagination of the reader.
This is a trick that writers use to make readers more involved in the story line and character development, and in this case, it works to their advantage.
Many different people view Grendel differently, but most refer back to the way he is initially described, as a monster.
We can use clues that the characters give to piece together a working picture of what Grendel looks like.
The main events such as: the long night feast in Heorot and the death of Beowulf, Grendels attack, Dragon attack and Beowulf battles with Grendel and Dragon still happen in the movie.
The picture of a very strong hero, who is supposed to be the strongest human is illustrated well in both movie and poem.
Then, the movie cuts out a mighty prince mourning of Hrothgar and replaces it by a preparation for a revenge and Hrothgar not only feels fear and sorrow as much as in the poem but also he stays calm and seeks for a warrior who can kill Grendel.
Grendel comes to the Heorot twice in movie but his coming is up to three times in the poem.