Original: In the poem , Beowulf , a hero of the Geats , battles three antagonists : Grendel , who has been attacking the resident warriors of a mead hall called Heorot in Denmark ; Grendel 's mother ; and an unnamed dragon .
Simplified: In the poem , Beowulf fights three monsters : Grendel and Grendel 's mother , and later in his life an unnamed dragon .