HELENA and HERMIA are best friends.  HERMIA’s father wants her to marry DEMETRIUS, who is promised to HELENA but who has fallen in love with HERMIA.  HERMIA wishes to marry LYSANDER and has therefore eloped to the woods to be with him.  DEMETRIUS has followed them, and HELENA has followed DEMETRIUS.  In this scene, PUCK has placed love potion in the eyes of both DEMETRIUS and LYSANDER, who now appear to both love HELENA.   She is freaked out by this and thinks that they and HERMIA have joined forces to make fun of her.   Although DEMETRIUS and LYSANDER appear in this scene, it is easily performed without them, as below.