Mal/Simon, on a backwaters planet in a little podunk town a doc and a captain need to be married to have respectable standing, otherwise the local toothless spinsters girls get dibs on them - with the local mostly-evil lord looking over their shoulders, and the business offer handing by a thread, will Mal and Simon find a way to seal the deal... without sealing themselves into an arrangement they won't be able to get out of?

(Or, you know, something just as chiched but better-worded. *cough*)