Santhoshathinte Onnam Rahasyam (Joyful Mystery) takes place entirely inside a car and that's the first metaphor that Don Palathara plays with; that all personal issues are closed and even when there's an external stimuli, it only makes things worse. Where this young couple is starting to fight over an unwanted pregnancy. You can relate to the arguments these two people have as you reflect on your own life and wait to see what could be the number one secret of happiness. By the end of the film, you find it out. Brilliant little film....