Lou and Penny have been best friends forever, so when Penny tells Lou shes sure tonights the night fiancé Mark will finally propose, Lou couldn't be more pleased for her. But when the moment arrives, Lou can't help but wonder if marriage might be the furthest thing from Marks mind, and Penny hasn't noticed a thing! Could it fall on Lou to break the news gently, or will Mark bend his knee before it's just too late?

