A writer's best ideas come from what if's and what would happen if's. Brainstorming exercises should always include a what if part. So take the premise of a friend's novel what if the boy you loved since high school was suddenly available and you had one night of passion with him. Then what if that passion resulted in pregnancy and he wanted to be involved. Sounds like a normal romance novel, but the idea is to throw in a twist which she does. What happens when the couple is threatened with miscarriage of the one thing that brought them together. Once in a Blue Moon by Celia Stuart www.liquidsilverbooks.com/books/onceinabluemoon.htm I had the great honor of helping read and critique this book prior to it selling.
So what's your what if? What if your brother would go to any extreme to prevent you from marrying someone else, including calling an old friend that you had a crush on. What if the person you thought was your true love but dumped you, came back into your life when you were engaged to someone else. Ah, I could go on and on.