A woman stands on a rooftop listening to the sounds of the city below. There is only the dull hum of traffic tonight. But she knows how easily that can change. It is usually the dogs who notice the sound first and begin to bark furiously. The noise of aircraft. Then the ominous percussion of explosions, a ball of orange rising from an airstrike in a familiar neighborhood.

The BBC has obtained footage and interviews from Tehran which evoke a city of strained nerves, of constant waiting for the next blast and relentless fear of the state security apparatus.

Baran – not her real name – is a businesswoman in her thirties. She is now too scared to go to work. With the start of the drone attacks, no one dares to go outside. If I open my door and step out, it is like gambling with my life.

She lives alone but is in constant communication with her friends. My friends and I message each other constantly asking where everyone is…and even when there is no sound the silence itself is terrifying. I am doing everything I can to stay alive and witness whatever lies ahead.

Like so many young Iranians, Baran saw her hopes of change devastated in recent months. Thousands of people were killed in a crackdown by regime forces in January after widespread demonstrations demanding change.

I cannot even remember how I used to live in the past without being reminded of the loved one I lost during the protests, she says. I fear tomorrow. I fear the person I will be tomorrow. Today, I survive somehow, but how will I get through tomorrow? That is the real question. Will I even live through tomorrow?

Now repression is total. Open dissent is impossible as the state's watchers are everywhere. Footage we obtained shows regime supporters driving through the city at night, flags flying from their cars – a message to any who might be tempted to protest.

Independent journalists still try to gather testimony that offers a credible alternative view, but they run the risk of arrest, torture, and possibly worse. As one of them told me: In wartime conditions you really don't know what they are capable of doing.

The situation is frightening…, says Ali, a resident in his forties. The skies of your country are controlled by enemy forces. But at the same time there is always hope in people's hearts. It's not that we are supporting America or Israel, but hoping simply that for one moment, something might happen that ends the current Iranian regime, and that the people will be able to create change.

Baran thinks the war may go on for years, and that its psychological effects will last even longer. This war will not end soon, because this war is inside our homes, inside the families…The war has entered our blood and has entered our lives.\