You might pass Servando "La Tuta" Gomez on the street and not look twice. But with a $2.5m bounty on his head, the charismatic leader of Mexico's Knights Templar drug cartel commands respect and fear.

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As we set off that afternoon, we knew it might all come to nothing. Our plan was to meet the men behind one of the biggest Mexican drug cartels, writes Thom Walker.

A group feared for its brutality and ruthlessness, whose members were being hunted down by the federal police, army, and now too by heavily armed vigilante self-defence groups who wanted to drive them out of the western state of Michoacán.

We had already made contact with his people, who helped guide us through the hillside villages to where our meeting was due to take place. Everyone there knows everyone.

An unexpected car approaching too quickly could easily be mistaken for the police - or worse - a rival group, and fired on by the Knights' armed guards at the entrance to every town.

Templar territory

We approached slowly, windows down, lights lowered. At each checkpoint, they already knew we were coming. The young men, mostly no older than 20, all waved us through with a cordial, "buenas noches".

There was no rushing this journey. It would take us as long they wanted it to. Word reached us that we needed to wait.

'From England, you say?' the elderly man asked me. 'I hear it's pretty cold over there.'

Halfway up into the hills, we stopped at a small kiosk to have a drink.

The evening was warm and the streets quiet. We sat on wooden benches and each drank a lemonade as the owner, a man in his 70s, chatted with us.

His son, whose young wife cradled their 18-month-old daughter, joined us too. "From England, you say?" the elderly man asked me. "I hear it's pretty cold over there."

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Trained killers

By now, it was pitch black and there were no other cars on the road. As we continued winding further into hills, we knew were getting closer.

Our fixer asked us to switch our phones off. Our interviewee was very careful, he warned.

We pulled up outside a house. By now, we had little idea which village we were in, but we were certainly deep in Knights Templar territory.

We had little idea which village we were in, but we were certainly deep in Knights Templar territory.

His men, each with a gun tucked into the belt of their baggy jeans, greeted us warmly, and offered us a drink as we waited.

Young, friendly, and funny, like many Mexicans I had met, it was hard to think that some of them were trained killers.

After several more hours, and much negotiation, we finally heard another car pull up outside. It was our man.

Servando 'la Tuta' Gomez

Servando Gomez, better known as "La Tuta", a former teacher turned cartel leader, had decided he would talk to us.

With a greying well-kept beard, a baseball cap and jeans, I think I had expected more drama. Ostentatious gold chains, or teeth, maybe even a sharp Armani suit.

But here he was, a man with a $2.5m bounty on his head, and he looked like someone you might pass on the street and not look at twice.

We could see his men looked up to him, surely feared him, and most of all knew that when he talked, he meant business.

As soon as he started talking, it became clear how he'd risen to this position, commanding around 10,000 men across the state of Michoacán and beyond. "La Tuta" oozed charisma.

He was charming, engaging, full of jokes, but with a commanding presence. We could see his men looked up to him, surely feared him, and most of all knew that when talked, he meant business.

Our conversation lasted well into the night. We talked about work, religion, Mexico, his family, life as a wanted man, his organisation.

And then a moment of humility from an otherwise often irreverent man. "The biggest narcos in Mexico," he said with a grin, "no-one knows them. The idiots are the ones that appear in public."

We had many more questions, but it was time to go. Back down the hillside, through the darkness, past the checkpoints and finally, back out onto the highway, somewhere in Mexico's wild west.

Thom Walker is a producer with Channel 4 News