Life has many ways of testing a person's will, either by having nothing happen at all or by having everything happen at once.

Brazilian novelist Paul Coehlo's famous quote succinctly sums up the pickle Dr Kevin Lee found himself in three years ago.

Things, he reckoned, were hunky-dory. Having bought out another founder, he and his business partner owned two dental clinics which seemed to be doing well.

But a new business manager they hired took a good look at their accounts and told them otherwise. In fact, they were in debt.

To tide things over, he and his partner used their credit cards to settle some bills.

It got worse quickly. Soon, they were mired in debt totalling nearly $100,000 and owed their staff at least four months' salary.

There were two options.

"Either we close one clinic to scale back, to reduce rental and sell equipment or we open another clinic because that was the only way to get a loan," says Dr Lee.

He took the riskier option and it paid off handsomely.

Today, he and his partner, Dr Loy Tsu Ken, employ 25 dentists and 40 nurses and own 10 Luminous Dental clinics in Singapore, and one in Bangkok. The plan is to open another five clinics here before the year is up.

Dr Lee says he owes a big debt to his nurses who gave him their faith, agreed to work without salary and helped to expand the group.

"That's why we really take care of them here and make sure we give them good opportunities and good career paths. We have to prove to them they made the right decision to stay," he says.

More about that later.

The boyish-looking 39-year-old is the youngest of three sons. His father is from Indonesia, his mother, from Seremban in Malaysia.

His father ran a provision shop in Joo Chiat with one of his brothers who has four children.

Together with Dr Lee's paternal grandparents, the two families - six adults and seven children - lived on the second floor of the shop which had only three bedrooms.

Toys were an indulgence the family could not afford but Dr Lee and his siblings and cousins romped happily among the trees and drains behind their house.

"Our parents did a good job of hiding poverty from us. We grew up in an environment where we thought we had a lot. We didn't know what was out there," he says.

It was not until he started primary school in Haig Boys' that he became aware that he was a lot less well off than many of his peers.

"My parents just told us to study hard if we wanted our lives to change in the future," he says, adding that he and his siblings had to help man the shop and make home deliveries after school.

In his early teens, the provision shop went under and his family moved to Telok Kurau.

He continued his education at Tanjong Katong Secondary Technical, where he became the leader of the school band. The gig, he says, gave him some precious lessons in human behaviour and leadership.

Dr Lee, who played the French horn, remembers pushing the members hard for a competition which they lost.

He recalls: "The team members broke down and some of them started blaming me: 'You pushed us so hard but we still lost.' It taught me many lessons about management. We need to have the right vision. That vision can never waver and the people at the top cannot give up. But at the same time, we must learn to accept defeat."

Dr Lee did well for his A levels at Temasek Junior College but did not get into medical school as he had hoped. "It was my mother's dream," he says.

Although disappointed, he accepted an offer to study dentistry at the National University of Singapore.

"All I knew about dentistry prior to university was from my experiences with the school dental service. I thought it was all about cleaning, filling and extracting," he says with a laugh. "The course wasn't that bad. It was actually quite fun."

He graduated in 2003 and worked in a SingHealth polyclinic for a while. He later joined the Singapore Armed Forces (SAF) because he felt it would make it easier for him to get into a postgraduate specialisation programme.

Two years later, he married his girlfriend from university, also a dentist. They hosted a wedding dinner for 400 guests at Carlton Hotel and set up home at an executive condominium in Yew Tee.

Barely three months later, the couple annulled their marriage. He declined to go into reasons but said it hit him like a bolt.

"I remember packing all my belongings in a car and going back to my parents," he says.

The next couple of years passed in a haze; he found it hard to climb out of the funk he had fallen into.

"I didn't want to work and meet friends. I didn't know who to talk to. I turned up late for work and was not interested in anything at all. I was really disoriented. My record at SAF was bad," he says, sheepishly shaking his head.

His plan to sign up for a specialisation programme was abandoned.

"People who got into the speciality programmes got upgraded. I got stuck," he says.

His condition prompted his boss to send him on a few humanitarian trips with the US Army Dental Corps to countries like Indonesia and Thailand, hoping they would help to clear his mind.

"It was quite eye-opening to see how they work. When you have willing people and volunteers, and you work with passion, everything will fall in place even without flow charts and action plans," he recalls.

In 2007, just before the completion of his bond with the SAF, two good friends approached him and asked him what his plans were.

Although he had hoped to join a polyclinic or a dental group, he was not hopeful that he would get offers as he was not so clinically adept any more.

"They asked me: 'Since you have nowhere to go, do you have any money?' I said: 'A bit.' "

Each of the partners forked out $30,000 and set up the first Luminous clinic in Chai Chee. With a grin, Dr Lee says they took the first shop unit they were shown.

"When we were about to sign the lease, we found out there was another clinic next to us. One of my friends was bullish and said: 'We just have to work harder, open longer and charge cheaper.'

"So we signed, went to have coffee to celebrate and found out there was another dental clinic behind our unit. That's how green we were. We did not do our due diligence. It was quite hilarious," he says.

More money was needed to buy equipment, and Dr Lee's savings, considerably less than his partners' because of his divorce, were soon wiped out.

"The two of them wrote me a cheque for $10,000 and told me it was for my household expenses and to take my parents out to eat," recalls Dr Lee, who kick-started operations while his two partners stayed on in their jobs. They joined the business about two years later.

Their "work harder, open longer and charge cheaper" strategy worked. The shop was profitable from the first month. All was well for the first few years.

In 2010, he married a former flight attendant with whom he now has two children, aged six and four.

Four years later, he and his partners decided to open another clinic in Bedok.

That same year, one of them left.

"The separation was amicable. We bought over his shares and thought it was a fair valuation," he says.

He and the remaining partner, Dr Loy, then hired Ms Rebecca Tan, their former part-time dental nurse who had gone on to get a degree in business and marketing.

"She took over the accounts and within a few weeks, told us that we were in trouble. How could that be? I thought we were profitable. But she said we had a $60,000 invoice for tax and GST and there was no money in the company account," he says.

It was, Dr Lee says, the scariest episode in his life.

"Ken has two kids, I have two kids. We also had four dentists, five nurses and two clinics. It was the middle of the year and there was a bonus coming up for the nurses. Ken and I didn't know what to do; we were clueless."

He adds: "The turning point came when Rebecca talked to the nurses. I don't know what she said to them but they said 'no' to the bonus and agreed to do without pay for the next few months."

Now Luminous' global head of operations, Miss Tan, 28, says: "Kevin and Ken were like big brothers to me, so I really felt I had to help them out. When I talked to the nurses, they were naturally hesitant. A couple of them needed the money to send home to families in Malaysia and the Philippines.

"But Kevin had treated them well. One of them was a former hairdresser whose pay was doubled when she joined Luminous so she agreed out of gratitude. I also told them if we worked together, we could pull through."

The situation forced Dr Lee and Dr Loy to buckle down, do their research and decide on their next course of action.

"We took a higher than normal loan after exploring the market and finding out that there were some financial instruments which catered to the dental industry and came with a lower interest rate."

With that, they opened another clinic in Tampines. Things stabilised after that, allowing them to take a breather.

It was time, says Dr Lee, to think of the nurses who had taken "a few bullets for them", with some even turning down offers from other clinics.

Perks like company holidays were important but concrete career paths, they decided, were just as important.

The company invests a lot of time and money in training.

"If we hire them and do not train them, we are not doing right by them. We have to give them opportunities, carve out career paths," Dr Lee says, adding that the nurses now run the show from human resource to logistics.

The first dental nurse they hired, Madam Jasmine Koh, is now the company's head of logistics, while another, Ms Jessia Pua, is now head of Singapore operations.

Between 2014 and last year, they opened two more clinics.

In fact, things turned around so dramatically for them that there were several multimillion-dollar offers to buy them out. Accepting any of them could have made him and his partner very comfortable.

"We did think about how we could give some of the money to our parents and our nurses. But it would mean giving up majority (share), and we didn't want that. We didn't want to lose our identity," he says.

Last year, things took on an even more interesting twist. A friend introduced them to Cap One Financial, a boutique investment firm.

When Dr Lee met Ms Yuanita Tjia, the managing director, he had a good laugh.

"She had been my patient for a few years. She knew our environment, what we were about."

Now a partner and a shareholder, she got on board other investors who pumped in several millions in the company. Within half a year, Luminous opened another six clinics, all of which are profitable. Many of them have just one treatment room each, but some are centres with X-ray facilities and special children's treatment rooms.

He declines to reveal figures but says that revenue has increased 20 per cent month on month in the first three months of this year.

Although there are plans to open more outlets, he has no plans for Luminous to become too big.

"It will be hard for us to keep our identity. But if we grow organically, we can preserve what we have."