They appear when Shrek and Donkey just saved princess Fiona, and were walking in the forest. Suddenly Robin Hood appeared along with his Merrymen in attempt to kidnap and "rescue" Fiona. When they have beaten Shrek and Donkey, Fiona starts attacking them until they all are defeated. After their defeat they quickly escape.
They later appear in Shrek Karaoke Dance Party singing the song YMCA.
The band of merrymen reappear with Monsieur Hood as zombies possessed by the beat of music. Monsieur Hood, with now pale skin due to listening to the beat of the music also appears as a zombie.