D-Day is almost here! The stage is set and all roads will lead to the O2 for The Unforgettable Tour on August 24. Observer columnist DEVANSH PATEL brings you the excitement, the anticipation and the sleepless nights from the Londoners who are on the verge of attending Bollywood's biggest, best and most unforgettable night out ever

It's been a long and a tiring tour ever since it kicked off on July 18 this year but what's vital is that it's been an unforgettable one so far.

But hold on....it's not over yet. After putting on spectacular shows in Toronto, Trinidad, Los Angeles, San Francisco, Houston, Chicago and New York, the Unforgettable Tour and Wizcraft - along with its stellar cast comprising of Amitabh Bachchan, Abhishek Bachchan, Aishwarya Rai Bachchan, Preity Zinta, Riteish Deshmukh, Vishal

and Shekhar - are ready to take centre stage at London's O2 along with a very special guest, London's favourite Celebrity Big Brother winner Shilpa Shetty, on Sunday August 24.

There are thousands of music tours in the UK alone in the summer months, bringing people together from a variety of backgrounds, cultures and places, attracted for the same reasons: the atmosphere, passion for the music and the thrill only experienced at such live events.

But there are two reasons for this tour to be even more special - Bollywood and the Bachchans.

Yes, this is by far the most expensive world tour that Bollywood has ever ventured into. So what makes such incredible tours a worldwide success? The answer is: its fans.

Whether you are a regular tour groupie or have been saving like crazy to get to that one special event this year, the tickets are the top most priority. Your only hope to get a glimpse of your favourite Bollywood stars is the ticket in your hand. No ticket? No show.

With so much said and written about The Unforgettable Tour and its performers, it's time now to listen to the ordinary fans who are shortly going to attempt the impossible; filling 20,000 seats at The O2 - a feat thought only possible for mega-stars such as Madonna, Elton John or Michael Jackson.

Anil Mehta, a father-oftwo from Harrow, told me: "The word 'impossible' never exists in Bollywood. I am sure we will manage to fill the entire arena with our love and undying support for the film industry which we have seen grow with us since our childhood days.

"It all goes to show how much has Bollywood inspired us over the years. It's pay back time for us now."

But Nikita Poddar, a lawyer from Wembley, had some doubts: "To fill 1,000, 2,000 or 5,000 seats isn't a problem. We've seen that happen in many shows at the Wembley Arena.

"Here we are talking about The O2. It's going to be an uphill task."

Well, as Rose Kennedy - matriach of the Kennedy dynasty in the US - put it: Life isn't a matter of milestones, but of moments. And many Bollywood fans want their moment at the O2.

Rohan Shinde, a loyal Bollywood fan and regular at Harrow's Safari Cinema in Station Road, stated: "I've never missed a single Bollywood film in the three years since I came to the UK. There is just something which attracts me towards Bollywood. I like the colours, the songs, the fights, the clichéd romance, the melodrama and, last but not least, Amitabh Bachchan."

He added: "This man just cannot stop. Everytime I see Big B on screen, I learn a lot from him.

"The way he sits, the way he talks, the expression in his eyes - and his professionalism is mind-blowing."

One thing is becoming clear as I write this story; that Londoners are fascinated by the living legend Amitabh Bachchan, the 'baap' (father) of Bollywood as he is called, and will do whatever they can to get hands on those tickets to see their favourite super star performing in front of them.

Jatin Karia, owner and founder of Samskara, a health and beauty boutique in Harrow, said: "The first thing that comes to my mind when I hear the name Amitabh Bachchan is 'legend'. I've seen his film Sholay many times. I am a bit sad because I still haven't managed to get my hands on the tickets for the show. Now I have no option but to buy the VIP tickets. Big B is the only reason I'll be buying these tickets."

From the eight-year-old to the 80-year-old, everyone seems to be getting really excited and can't wait for Sunday to arrive.

Tina Roberts, from Kenton, has relied on lots of caffeine since last week to help her rehearse her steps.

She said: "It's bizarre but I am going to dance my way out on all the songs which will be performed by the actors.

"I've got the cheapest tickets of the lot which means that I'll be right at the back. I'm having coffee all night and rehearsing the songs by seeing the DVDs of these songs. I can't wait for Sunday."

Eight-year-old Anusha, from Pinner, said: "I liked Bhoothnath a lot. It's my favourite film. I want to see little kids dance too along with Amitabh uncle."

Big B undoubtedly seems to be the biggest reason why people are attracted towards this mega show.

A newsagent from Harrow informed me: "Every other Asian coming into my shop enquires about the tickets for the Unforgettable Tour and I have to sadly tell them that they are not sold here. Such is the demand for the show."

Sonali Patel is excited too: she is one of the lucky ones going.

She said: "I am going to see my favourite Abhishek Bachchan sing his rap song Right here right now from his film Bluffmaster. He is so cute yet handsome. I like his style of dancing."

Bhavna Talwar from Sudbury said: "I am not going for any individual but for all of them. It's nice to see how the organisers Wizcraft have managed to put on such a big show.

"Roping in Shilpa Shetty, the Bachchan trio and other A-listers from Bollywood wasn't going to be that simple. I think we all should raise a toast to Bollywood for giving us endless entertainment for almost a century now."

Whichever star you are going to see, one thing is definite. The Unforgettable Tour is bringing different nationalities from different countries together - something our politicians could not do in all the years since India's independence.

After all, Bollywood is all about love, laughter and life's lighter side.