Bombay is India's largest, most cosmopolitan city, officially home to 16,000,000 and probably a lot more the government would rather forget about. A traffic-circle intensive city plan, grandiose Gothic architecture, clocktowers and double-decker busses show lingering influence of British rule. Simultaneously India's richest and poorest city with an almost non-existent middle class, Bombay is home to both Bollywood stars and the largest slums in Asia.

Chris, Mary and I spent our short time together exploring this city of contrasts by visiting its nicest neighborhoods and worst slums. We hired a driver named Hussein, whose English ability was surpassed only by his ability to take us exactly where we wanted to go.

First stop, Raey Road. Tiny corrugated tin shacks sloppily smashed together overtake sidewalks and pedestrian bridges. Private lives inside visible through open doors and uncovered windows; families watching TV, cooking meals over open fires, nursing babies, seemingly oblivious to the crush of humanity both inside and outside their dwellings. Life spills out into the gutters; bathing, eating, washing, shitting. Leaning ladders lead up to wobbly second levels. Colorful laundry hangs to dry, piles of red tomatos, brightly wrapped candy and snacks are displayed for sale. Women in saris chase naked babies out of doors, within feet of the constant rush of traffic. Families pay about 500 rupees per month (about $12) to inhabit spaces smaller than your bedroom.

We get out of the taxi and take a walk along a bridge that Hussein claims was captured by these rural poor, most of whom are not from Bombay. A throng of small children too poor to be in school on a Wednesday gathers around us. Not accustomed to seeing tourists, not one asks for anything. They want only to be noticed, to say hello, to shake our hands, to ask our names, to follow us. Their smiles are brilliant. They seem so happy, so content. This is life for them as it always has been. I don't feel sorry for anyone. I am aghast and alarmed, overwhelmed and curious, never worried for my safety and only slightly claustrophobic in the crush of attention.

Next stop, Worli, a small neighborhood along the waterfront that's home or second-home to some of the city's international elite. Tall apartment buildings and single-owner bungalows line the promenade, occupying some of the city's most expensive real estate. I think most of them look terrible, mostly architectural disasters in dire need of paint jobs. There are virtually no people in sight. We quickly move on. There's no energy here.

Next stop, Dharavi, the largest slum in all of Asia. Smack between a high-tech business district and an upmarket suburb, the slum is home to 600,000 of Bombay's residents. There are people everywhere and they look at us kindly, gently, inquisitively. We squeeze past wide-eyed children and duck under stolen powerlines hanging low over tiny narrow alleys. Stepping over fly-swarmed open sewers, we peer into doors and see life and work in action. Cloth dying, pottery making, tailoring. Blue, green, pink, brown painted walls.

A man washes clothes in a pool of murky wastewater. A small boy squats to take a bowel movement in a sewer by the side of a main road. He is still there when we pass by again 10 minutes later. Goats rifle hungrily through heaps of garbage. A neverending stream of human waste feeds an opaque, gray river in a deep canal below the front doors of people's homes. Makeshift tin shanties are held together with asbestos sheets, old canvas, bamboo, old tires.

Final stop, Bandra, a rich neighborhood on a small peninsula where we find Bombay's most expensive hotels and big houses that are home to some Bollywood stars I've never heard of. People are dressed nicely, wearing glasses and driving cars, demonstrating the clear marks of India's economic elite. We sip mochas at a waterfront 'Barista,' India's answer to Starbucks. I find the views mediocre and most of the houses rather ugly. I am not impressed and lose myself in images and thoughts from the slums. I am still processing what I saw and felt, but know I will never look at life through the same eyes.

Today Chris and I said goodbye to Mary as she moves on to Delhi to meet her parents. We will be on a train for the next 17 hours en route to Udaipur, Rajasthan.