When night came, "Grendel / [w]ent up to Herot, wondering what the warriors / [w]ould do in that hall when their drinking was done" (Raffel 31-32).
when the time was right, he entered the mead hall ready to attack.
Upon entering Herot, "[h]e found them sprawled in sleep, suspecting / [n]othing, their dreams undisturbed" (33-34).
in the quiet of the night he "[s]natched up thirty men, smashed them, [u]nknowing in their beds and ran out with their bodies, / [t]he blood dripping behind him (37-39).
When Hrothgar woke the next day, " a mighty prince [was] mourning / [t]he fate of his lost friends and companions" (45-46).
All who were present were "learning / [t]he beginning might not be the end" (48-49). They would soon find out that they were right, i was just the beginning of 12 long and miserable years of Grendel's revenge.