William Rodriguez, 40, was the last person to escape the World Trade Center as the second of the Twin Towers collapsed on 9/11. Here he tells his extraordinary, shocking and deeply moving story of how he helped to save countless lives, and how he owes his own survival to a series of almost unbelievable miracles:When the first plane hit the Twin Towers, I was in the basement, two storeys underground. My job was cleaning the stairwells, and I was talking with my supervisor when the floor seemed to erupt beneath our feet.The false ceiling collapsed in on us. The sprinkler system began spewing water everywhere. And the 12 people in the office with me started screaming.My first thought was that a generator or some other piece of machinery must have exploded. There were no windows on our floor, and we had no way of knowing what was happening above us.Within about seven seconds, the tower was rocked by an even louder blast, and we could feel the entire building begin to twist. It was designed not to be rigid, so that it could withstand high winds by oscillating, but now it was moving so violently that the walls were cracking. I could hear the concrete and metal coming apart, even over our screams.A guy came staggering into the room, coming towards me with both arms extended. ‘Explosion, explosion,’ he was yelling.He seemed to have clothes hanging from his fingertips, as if he had not finished taking off a pair of shoulder-length gloves.As he came closer, I realised to my total horror that the ‘fabric’ was his skin. His burns were so extreme that, down the length of both arms, his flesh was peeled raw. I couldn’t process what I was seeing. William Rodríguez was a janitor at the North Tower of the World Trade Center. He was working during the attacks on September 11, 2001 The World Trade Center south tower is engulfed in flames after being struck by hijacked United Airlines Flight 175 William, left, carried firefighter Salvatore Giambianco to safety on a gurney after he joined rescuers digging survivors out of the rubble People walk away from the World Trade Center tower in New York City, September 11, 2001And then he turned his head, and the skin all down one side was hanging loose, exposing the bone.People were shrieking and backing away from him – not just because he had the most horrific injuries imaginable, but because of the blood. He was bleeding from everywhere, and his shirt was soaked in it.This was 2001, and many New Yorkers still had a phobia of blood, because of the Aids epidemic during the past two decades. I didn’t know the man but all my instincts were compelling me to help him.I ran into the office stockroom and grabbed boxes of paper towels. The whole basement was shuddering under my feet. At every moment, I thought we were going to be buried alive. Most of the people down there with me were temporary staff, who had no idea how to escape – the place was a warren of tunnels.As I was wrapping the guy’s arms in paper towels, he told me his name was Felipe David and he came from Honduras. His job was filling the vending machines. Another man, my friend Kenny Johannemann, helped to lift Felipe on to my back, and I told everyone to follow me, through the corridors to the loading dock and out through the bay for the delivery lorries.In the street outside, everyone was standing and staring upwards with their mouths open. I heard a voice crackling on a security guard’s radio, saying a plane hit the building.I could see the hole, and the smoke, and that was the first I understood of what was happening. I saw what I believed was debris falling. Later I discovered it was people leaping from the flames.If the plane had hit on any other day, I would have been dead. That September morning in New York City was so beautiful, with clear blue skies, that I took a chance and called in sick. But my supervisor had other ideas. He yelled at me till I agreed to go in.I arrived about 30 minutes late for my shift. Each morning I started by taking the elevator to the employees’ kitchen at the Windows Of The World restaurant on the 106th and 107th floors, where I could have a free breakfast. Then I’d work my way down more than 100 flights of steep stairs, cleaning as I went.Everyone in the restaurant lost their lives after American Airlines Flight 11 crashed into floors 93 up to 99. If I’d been on time, I would have had no chance of survival. Probably many of the people I helped to save, including Felipe David, would also have died. Emergency personnel tend to injured people in Liberty Park People evacuate the World Trade Center in New York City on 9/11We lived because I came in late, something that almost never happened.I’d been working at the Twin Towers as a cleaner for 20 years. I’d survived the previous terrorist attack in 1993, when a truck bomb exploded in the underground garage, killing six people and injuring more than 1,000 more. I was trapped in an elevator that day and the terror of it had haunted me ever since.The thought that people I knew were trapped now in the North Tower was overwhelming. I ran back into the building, and one man told me he could hear screams from the freight elevator shaft in the basement.I put my ear to the doors and I could hear two people, yelling for help. ‘We are going to drown!’ one was shouting. That made no sense to me. But I found a metal pole, and prised the doors apart, and then I understood – all the water from the sprinklers on every floor was gushing down the shaft.And the elevator, with a mesh roof, was trapped at the bottom, with the water already waist deep.All my life I had been an atheist. But at that moment I began praying desperately: ‘Please God, help me save those people.’ There were ladders in one of the storerooms, so that’s where I ran, though I knew they were always chained up. Incredibly, one of them wasn’t – and it was the longest one.Somehow I managed to drag that ladder to the shaft, climb down to the elevator, prise the mesh open, reach down and lift both of those people out. I will never know where I found the physical strength.After I got them outside, the police tried to stop me from re-entering the building. I started yelling in Spanish, which confused the cops so much they let me through.Inside, one of the Port Authority officers recognised me, and hailed me: ‘Willie, do you have the key?’I realised what he was saying. On every level of the stairwells, there were doors into the offices, but these were kept locked. Now people were trapped on those floors, because the elevators were not working, and they couldn’t get out into the stairwells.And I had one of the only master keys. The reason I had it was miraculous in itself: five years earlier, I fell down a flight of steps while cleaning and broke several bones. Nobody heard my shouts, because nobody ever used the stairs. Smoke pours out of the World Trade Center towers shortly after being struck by hijacked commercial aircraft Rubble is seen in the aftermath of the 9/11 attacks William later received several awards for heroism after he helped to evacuate many of the survivorsAll the doors were locked, and I had to drag myself up several flights to reach help. After that, I insisted on having a key.It was as though my accident that day was preparing me for September 11. The officer took me to the lobby, where the New York firefighters were arriving in all their kit, which weighed close to 100lb. They had the gear to break down those doors. But a key is much quicker.I led the way up those stairs, opening doors as I went, and by the time I reached the tenth floor I realised the firemen were finding it very hard – because tough as they were, they were in boots and helmets, carrying all their equipment, and I was just wearing overalls. Plus, I climbed those flights of stairs every day.We got word of a paraplegic guy in a wheelchair on the 27th floor who needed to be carried down. By the time we got up there, the firefighters were really sweating under all their gear.One of them asked me to fetch water for the men. I showed him the vending machine, but I didn’t have a key for it... so he kicked in the glass front. My reaction was totally irrational: I told him, ‘Don’t do that! I’m Puerto Rican, you’ll get me arrested.’He told me that was the last thing I needed to worry about. But I never forgot that moment, because a lot of Hispanic survivors of 9/11 got a rough deal later.I carried on climbing, as fast as I could, opening the doors. On the 33rd floor, there was a woman in bare feet, in a red dress. I’ll never forget her. She said, ‘I don’t know where to go. I’ve worked here two weeks, what are we supposed to do in an emergency?’ The next time I saw her – well, I’ll come to that later.Heading back to floor 27, I volunteered to help one of the firemen carry the paraplegic man, whose name was Ed Beyea, to the ground floor. As we went down, I could hear screams for help inside one of the elevator shafts. The firefighter just looked at me and shook his head. There was nothing we could do.At that moment, we were hit by a blast so huge, it felt like the building was imploding. That was the South Tower collapsing.Ed was wearing an oxygen mask. His eyes were bulging out of his head with fear. I kept talking to him, telling him we were safe, it was all fine. ‘After this, we’re going to go get a beer,’ I promised. Strange, the things you say... I don’t even drink.We got Ed down to the lobby. The dust was so thick, I could hardly see, and it burned my skin, my eyes and my lungs. The firefighter told me to go and get an ambulance ready. There were no doors or glass frontage, it was all gone. Emergency personnel tend to injured people in Liberty Park, New Jersey, in the aftermath of the attack The New York City skyline almost completely covered in smoke after the Twin Towers were hit William is now an advocate for 9/11 survivors, serving as president of the Hispanic Victims Group As I came out into the open, all the police, the Press and the bystanders were yards away, behind a cordon of yellow tape. A cop was yelling at me, ‘Don’t look back’.I did look back, of course. What I saw was more horrific than anything I can describe.The bodies of people who had fallen from the burning floors, hundreds of feet up, were scattered across the sidewalk but they were barely recognisable as human remains. Their bodies had disintegrated on impact.And right beside me was the woman from the 33rd floor in the red dress. She was sliced in two, diagonally, from her neck to her hip. I can only speculate that she was hit by falling glass, like a guillotine.I stood there, stunned, until I realised people were yelling, ‘Run! Run!’ and the earth began to shake. I looked up and the building seemed to be shifting sideways. There was a fire truck right in front of me, and I threw myself under it, as the tower collapsed.The rubble buried the truck. I was in complete darkness, with only a pocket of air. I was certain I was going to die, and I started to pray that when my mother saw my body, it would look like I died peacefully.When I first came to the US as a young man, I had dreams of being a professional magician. Escapology was one of my talents. Harry Houdini himself could not have got out from under that rubble, but I did know Houdini’s tricks for slowing my breathing and my heart rate, to make the air last as long as possible.A news crew had seen me dive under the fire truck. Rescuers managed to clear a path to where I was buried – but when I first saw their lamps, blazing through the dust, I thought I was dying and their lights were heaven. They gave me oxygen and it was 15 minutes before I began to understand I was still alive.Someone stuck a microphone under my nose and asked me how I felt. And someone else gave me a workman’s yellow tabard, because my shirt was in shreds. The vest made me look like one of the rescuers, so I joined in, helping to dig people out of the rubble.I found one of the firefighters, Salvatore Giambianco, trapped under debris but still alive. There’s a photo of me helping to carry him to safety on a gurney. I’m very proud of that image, and of the yellow vest, which is now framed on my wall.My life changed for ever in many ways that day. I became an advocate for 9/11 survivors, serving as president of the Hispanic Victims Group. Many of them were immigrants without papers, and I’ve spent 25 years campaigning to win them the right to remain in the US and the economic assistance they deserve.And one of the reporters who interviewed me was a woman named Elizabeth, from a news show in Ecuador. We fell in love, got married – and we’re still happily together today.