You chant a song of peace.  A number of intelligent creatures up to your spellcasting ability modifier who can hear you must make a Charisma saving throw or become friendly (not necessarily to you, just friendly).  This spell has no effect on creatures in combat or Chaotic Evil creatures.  If a creature under the effect of this spell engages in combat or has reason to become hostile towards you or one of your allies, the spell ends on that creature and its allies.  Any creature that is immune to being charmed is immune to this spell. 

At Higher Levels.  When you cast this spell with a spell slot of 2nd level or higher, the number of creatures you can target with it increases by an amount equal to your spellcasting ability modifier per level above 1st.