1) Medea writes Jason a letter expressing her anger over him leaving her for another woman after all she had done for him, including helping him obtain the Golden Fleece and killing her own brother. 2) She details her plan to get revenge, which involved giving Jason's new wife a poisoned dress that killed her and also the king. 3) Medea admits to later killing Jason's children as well, saying it was a necessary sacrifice, and hopes Jason now feels dumb for unwittingly helping with her plan for revenge.