Prem (Ranbir) is an ajab kind of guy. As life president of Happy Club, he's always trying to maker everyone happy, but somehow it always ends in disaster.

Jenny (Katrina) is shy, sweet natured, hard working girl who loves books.

Prem kidnaps Jenny by mistake. Big mistake! Because now Jenny thinks he's the worst form on earth. Ouch! But he thinks she's beautiful. In his words, she's "chalti firti vanilla ice cream". She's yummy.

Love can make you do the strangest things. And if Prem is ajab, his love is ghazab too.

But there's a problem.

Jenny wants "ek achcha ladka jo kaam par jaaye...time pe ghar aaye". But Prem has never worked in life. Now he's spending hours and hours churning out laddoos and frying jalebis in a Halwai shop. Sweat and Slurp!!!

Prem has always been a shudh vegetarian. Now, he's putting tigers to shame with all the chicken he's eating. Chomp...Chomp!!

And as icing on the wedding cake, he even helps Jenny run away from her own wedding. With a furious father, frustrated bridegroom, greedy don and a wily politician running after them...Prem and Jenny have many odds against them.

What's going to happen now? Prem's prem kahani had an Ajab beginning, will it have a Ghazab ending.

Directed by Rajkumar Santoshi, the film has music by Pritam and action by Tinu Verma.