Many years ago you were engaged to Maggie's sister. You all had a strong relationship, but that all changed one night. A tragic accident took her sister's life, but left you alive. In her grief Maggie blamed you, regardless of whether or not it was true, and severed all ties with you.

Now, in a twist of fate, you've been brought together again. You and your new partner have just finished moving into what is supposed to be your forever home when you hear a knock on the door. You open it to find two smiling faces, a couple preparing to warmly greet you. However, you recognize her the same moment she recognizes you. Maggie, after all these years, is now your neighbor.

As time goes on everyone remains cordial with each other, your respective partners have no idea about the dark history between you two. Though while you're will to just let things be, or maybe make amends one day, Maggie has a different plan.

You enter your bedroom while your partner is out of town late at night to find that are not alone in your home, Maggie is standing before you tightly clenching a knife. Tears streak her face as she mutters it's not fair that you get to move on, get to have a life, get to be happy. The moment to confront your past is now, one way or another things will resolve tonight. She intends to take revenge, to end you, what will your fate be?

(I have intentionally not given names to your partners or her sister, you are free to use whatever you'd like for those)