Media playback is unsupported on your device Media caption Taralika Lahiri has been working in the private detective industry for more than 25 years

Weddings in India are big occasions - more so than in other cultures. Families save for their whole lives to pay for this one special event, which very often runs into days of celebrations with thousands of guests.

With so much invested in the extravaganza, it is common for a family to hire a private detective to check up on a prospective bride or groom before the ceremony.

And India has a wealth of pre-matrimonial detective agencies set up to check out people's past relationships, earnings and family history.

Fifty-three-year-old Taralika Lahiri joined the profession in 1987. Without any formal training, she learnt most of her skills on the job.

She then set up her own agency, National Detective & Corporate Consultants (NDCC) in 1994, with an initial investment of $5,000 (£3,000) provided by her family.

Image copyright Thinkstock Image caption Weddings are big business in India - so families don't want any nasty surprises about a prospective spouse

In 1987 she was one of only a handful of women in the field. Now, she says, it is a popular job for a woman.

Demand for female detectives is growing mainly because women are the top clients for matrimonial investigations and they feel comfortable hiring other women to do the snooping.

Online fraudsters

Taralika started out as a one-woman operation but now employs 15 people and says business is thriving.

"One reason pre-matrimonial investigations have grown in India is because increasingly marriages are being fixed on the internet.

"Before, we all had a network of aunts who knew eligible girls and boys and would fix up their matches. Now, you could be dealing with anybody with a false profile - he or she could be in India or abroad."

Families want to be sure that the man or woman chosen for their daughter or son is genuine and not a fraudster.

Image copyright Thinkstock Image caption Is your loved one everything they claim to be?

She recalls a case where a wealthy industrialist based in Delhi hired her to find out more about his daughter's boyfriend.

The prospective son-in-law always wore designer clothing, drove luxury cars, and arranged to meet in expensive cafes. The family grew suspicious and wanted his financial background checked out.

After weeks of following him around, Taralika's team discovered that he was a scam artist who had faked his address and hired cars to fool the girl.

Proof needed

Taralika says it can be tough to tell a young person that the bride or groom they are set on marrying is not who or what they appear to be.

It is important to collect hard evidence such as photographs and phone records to convince clients, she says.

Image caption When Taralika first started her agency, she was a one-woman operation

While pre-matrimonial enquiries dominate her portfolio, post-wedding disputes are also providing more and more business.

Divorce rates in India are on the rise. When marriage spats get ugly and head to the courts, both parties look for evidence to back up their claims, which often revolve around extramarital affairs.

Lawyers, too, often hire investigators like Taralika to get the right evidence to support their case.

"It's often a matter of reducing the alimony or getting the custody of a child, but the court wants solid evidence to prove the case," says Taralika.

Undercover filming

She cites a case where a non-resident Indian living in the US hired her to spy on his wife.

His wife had filed a case demanding a huge alimony, citing her inability to work as she was paralysed from the waist down and needed the money to take care of her kids.

The husband knew she was travelling to a wedding in Delhi and provided all the relevant details to Taralika.

So Taralika's team went undercover to the wedding venue as photographers and caterers. When the woman arrived, in typical Indian wedding style, she danced as part of the procession for the groom's party.

Taralika's team filmed the whole event and sent it as evidence to the US court dealing with the divorce. That sealed the case for the husband.

Image caption New technology has helped private detectives with their work

Costs for the agency's services vary on a case-by-case basis, but Taralika says a general pre-matrimonial investigation costs about $500.

A post-matrimonial investigation would usually be "much more" though, as you tend to have to gather more evidence.

'Intuition and hard work'

Taralika says things have improved in the profession from when she first began working as a detective.

Now there is much more technology at hand, such as high-resolution cameras with night-vision lenses, and hidden recording devices that fit on your glasses or pockets.

And with the right training, her employees can mine data from the internet to gather information from public records.

But while gadgets have made her life easier, she says that nothing beats "old-fashioned intuition and hard work".