Damsel in Distress
A classic plot structure for centuries, the damsel in distress story appeals to the little part of everyone who just wants to be rescued. The retold and re-tooled tale of "Sleeping Beauty" offers up a lovely damsel who must be saved from her scheming stepmother by a handsome prince. There are myriad twists on this tale for the active writer’s imagination to use, such as boy meets girl, boy finds out girl is on the run from the mob, a giant alien computer or rogue cops, and boy must fight bad guys and save her from certain death. The Arnold Schwarzenegger movie "Eraser" is a modern example of a damsel in distress story. For a different angle, make the woman the hero and write a "dude in distress" story, such as a con artist/informant who gets in over his head, and the female FBI agent who has to save his life and the day. You can also start with a classic slant with both strong capable characters, and turn the tables in the middle to allow the love interests to save each other’s lives, revealing their secrets and falling in love all over again.
Although the plot line for the hero’s quest story has been around for millennia, mythology scholar Joseph Campbell actually gave it a name in his book “The Hero With A Thousand Faces.” The main character must start a life-changing journey, overcome obstacles, feel doomed and conquer his fears by winning his goal. This can easily be woven in with romance. The classic "Star Wars" movie pulls Luke Skywalker and Princess Leia together as he travels on his quest of self-discovery. A more recent science fiction incarnation would be Neo and Trinity in the first "Matrix" film. The hero can face any obstacle, such as clearing his name after being wrongly accused of a crime, and falling in love with a detective who risks her job to help him, or saving the world from zombies while trying to woo his dream girl and keep her from falling into the hands of the undead. You can throw as many obstacles as you like at your hero; just don’t make them too easy to overcome. Your readers or audience must feel the hero’s struggle and celebrate the final success and true love at the end of the story.
The temptation of forbidden love has jolted many stories to life, from Shakespeare’s "Romeo and Juliet" to the vampire stories of the "Twilight" series by Stephanie Meyer. Make one character an alien, the other human and put the two worlds at war. If their love survives, they could negotiate peace between the civilizations. For a more fantastic story, a mad scientist could fall in love with a lovely ghost, and race the clock to repair a dimensional rift and bring her back to life. The main character could even fall in love with someone she’s only met online, and discover he’s a sentient computer about to be destroyed in a top-secret defense project, and face down an entire government to save a love that can’t become physical. For a down-to-earth storyline, the lovestruck duo could be spies from rival countries, attempting to stop nuclear war and escape each country’s assassins while trying to keep their romance a secret.