Neither an impregnable marriage vow nor a heartfelt love proposal is strong enough to keep a real-life relationship working on reel – at least it seems like that to me. Even sensational couples in reality don't seem to create much sensation at the box office when they come together.

Take Kareena Kapoor and Saif Ali Khan, for instance. I think that with the entire media hype around them, they could easily pass off as the most sought-after couple, after Brad Pitt and Angelina Jolie. But when they come together on screen, the sizzle is somehow not translated there or is done wrong. Tashan? Gosh, let's not even get there!

Ditto with Deepika Padukone and Ranbir Kapoor. I personally think they look cute together. However, I must admit that their combination in Bachna Ee Haseeno was not really a great idea!

Kajol definitely broke the hearts of many fans – men and women alike - when she decided to move out of the Bollywood fraternity after tying the knot with Ajay Devgan. We were all glad when she announced her return to films. But Raju Chacha was a terrible comeback. And to think that her chemistry with her own husband was pathetic! It hurts. The more recent U, Me Aur Hum was no exception either. Stolen from the very beautiful Hollywood flick, The Notebook, the Hindi version had no appeal – neither did the couple.

Akshay Kumar, in the good old days, sent temperatures rising with Ayesha Jhulka, Raveena Tandon and Shilpa Shetty, and has now accomplished the same magic with Katrina Kaif, Priyanka Chopra, Kareena Kapoor and so on. But with wife Twinkle Khanna, he was ice cold in movies like Zulmi and International Khiladi.

Beauty queen Aishwarya Rai looked very pretty in Kyun... Ho Gaya Na. But, her pairing with her then boyfriend Vivek Oberoi was not so pretty. It was the same case with hubby Abhishek Bachchan in Sarkar Raj, Umrao Jaan, Kuch Na Kaho and Dhaai Akshar Prem Ke. With all the news around the junior Bachchans at the time of their marriage, the last thing people expected to see was a lack of onscreen chemistry between the two love birds.

Then again, there's the steaming hot John Abraham and Bipasha Basu. We have to agree that together, they create news off-screen. But, together, onscreen, they are often a tragedy. Dhan Dhana Dhan Goal, Madhoshi, Aetbaar – all bad!

It feels funny when I think of Kareena and Shahid Kapoor's chemistry. When they were blindly in love, in real life, they made disasters like 36 China Town and Fida. Once they broke up, Jab We Met was born. Sigh! Somebody please explain to me how this happened.

My wild guess is that for a couple to be successful onscreen, they should break up in real life. Okay, that's really evil! Let's get logical here. Irrespective of how much the couples are in love, the movie makes a difference only when it is made well. However, good chemistry is more like a cherry on the cake – while it's not particularly necessary, it is definitely preferred.

P.S. - Now if we slyly do a bit of shuffling among these couples, they work magic. Like say, Kajol with Shahrukh Khan, which is an evergreen choice, Saif with Rani Mukherji, which is cool, Akshay with Priyanka Chopra, which is hot, and John with Priyanka, which is good too. And the winner of the best-chemistry list would be Aishwarya Rai Bachchan with Hrithik Roshan (much to Abhishek Bachchan's annoyance)! This list can go on and on... but sadly, it has no real-life couple in it yet.
That's the sad truth. Sob!