Iran is facing its most serious challenge since the 1979 revolution. Huge protests have erupted across the country. The government responded with a fierce security crackdown and almost complete internet blackout, a scale unseen before. Streets in Tehran, once filled with angry crowds, are growing quiet. "On Friday it was extremely crowded - the crowd was unbelievable - and there was a lot of shooting. Then Saturday night it became much, much quieter," a Tehran resident told BBC Persian. An Iranian journalist said, "You would have to have a death wish to go out now." The unrest is worsened by external threats. President Trump has warned of military action against Iran. This comes after US strikes on Iran’s nuclear sites last year and a 12-day war with Israel. Trump says Iran wants to return to talks, but he may act first. Iran won’t give in to demands like stopping nuclear enrichment, which is vital to its government. Experts say Iran's leaders want to survive the crisis by clamping down hard. Vali Nasr from Johns Hopkins says, "Their inclination is to clamp down, to try to survive this moment, and then to figure out where they go from here." Despite the crackdown, protests continue. Death tolls appear to be rising faster than last year’s protests that lasted over six months and killed around 500 people. Over 20,000 people have been arrested so far. Iran’s state TV admits some protesters have died and shows makeshift mortuaries. Government buildings have been set on fire during protests. Authorities blame "terrorists and rioters" and threaten death penalties for "vandals" accused of "waging war against God." They blame foreign enemies like Israel and the US for stirring trouble. The unrest began with traders striking over a plummeting currency and soaring inflation near 50%. President Masoud Pezeshkian promised talks and gave citizens a small monthly allowance. Despite this, protests spread from small towns to big cities, demanding economic and political change. Iran’s system is strained by sanctions, corruption, and social restrictions. Still, key parts of the government, including the Revolutionary Guards, hold firm. Supreme Leader Ayatollah Khamenei remains the ultimate authority. Outside intervention could boost regime unity instead of helping protesters, experts warn. Some Iranians back peaceful change from within. Exiled former crown prince Reza Pahlavi has called for US help and led some protest chants, but his support is mixed. Meanwhile, Iran’s old pre-revolution flag has appeared among demonstrators. The coming days will test whether Iran can contain the unrest or face deeper chaos. The future remains uncertain as anger burns in the streets.