Mukesh Ambani is teetotal vegetarian, whose wife describes him as quiet, modest and shy.
He lives in Mumbai with his partner Nita and has has two sons - Anant and Akash - and a daughter, Isha. He watches three Bollywood films a week - because "you need some amount of escapism in life".
He's also one of the richest men on the planet and the new owner of Hamleys toy shop through his company, Reliance Industries.
Overall, the 62-year-old is worth an estimated £42 billion, according to Forbes, making him the 13th richest man in the world.
His wealth comes from telecoms, oil and gas giant Reliance Industries - which made £70 billion of revenues last year alone.
Hamleys £70million sale - iconic toy shop bought by Indian billionaire
How he got here
Reliance Industries was founded by Mukesh's father Dhirubhai Ambani. Dhirubhai worked as a yarn trader, and incorporated Reliance Textiles Engineers in 1996.
But he didn't stop there, building his business interests and in 1973 launching his Reliance Industries empire.
By the late 1970s, Mukesh had earned a Bachelor of Science in Engineering degree from the University of Bombay and was off to Stanford Business School in the US to study when his father called him home.
The firm was growing, and he wanted his son to oversee the construction of a polyester mill.
The expansion didn't stop there - with suppliers as well as petrochemical plants and oil refineries also being bought up.
Telecoms firms were added, and gas exploration results were impressive too. Reliance Industries had become a giant.
In 2002, after Dhirubhai died, the firm was divided between Mukesh and his younger brother Anil.
The brothers split the business, with Mukesh keeping control over refining, petrochemicals, oil and gas and textiles operations, while Anil took on the telecommunications, asset management, entertainment and power generation parts of businesses.
Mukesh's empire continued to grow despite the split, now including a 4G network, broadband, logistics, media and retail - becoming India's larges retailer with around 1,500 stores in 2013.
Reliance currently employs 187,729 people.
Personally, Mukesh also has property worth more than £300 million - including a 27-story home with three hellipads and room for 600 servants - and owns the Mumbai Indians cricket team.
One report put his family home as the second most valuable on the planet - with only Buckingham Palace worth more.
What next for Mukesh Ambani?
India's richest man is currently making a play for what could become the biggest online marketplace in the world.
India's use of smartphones and online retailing has been soaring in the past few years, as the population gets better off and embraces a new way to spend.
The process has been accelerated further through Reliance firm Jio - which offers dirt cheap data packages over its 4G network. It has 306million customers.
The better news is that American giants like Amazon and Wallmart, or Chinese ones like Alibaba, don't have a firm grip on the market yet.
Mukesh has seen an opportunity - and is moving to take a position in India's online retail market.
The billionaire is quietly putting together a series of partners as part of his push for this business, which he thinks will be as important to oil and gas to his firm’s earnings within the next 10 years.
Hamleys, with its worldwide recognition, looks likely to be a part of that move.
