Right... but then:
The official pretext for the start of the coup was Mossadegh's decree to dissolve Parliament, giving himself and his cabinet complete power to rule, while effectively stripping the Shah of his powers.[7][8][9] It resulted in him being accused of giving himself "total and dictatorial powers." The Shah, who had been resisting the CIA's demands for the coup, finally agreed to support it.[7][8][9] Having obtained the Shah's concurrence, the CIA executed the coup.[62] Farmans (royal decrees) dismissing Mosaddegh and appointing General Fazlollah Zahedi (a loyalist who had helped Reza Shah reunify Iran decades earlier)[8] were drawn up by the coup plotters and signed by the Shah. On Saturday 15 August, Colonel Nematollah Nassiri,[8] the commander of the Imperial Guard, delivered to Mosaddegh a firman from the Shah dismissing him. Mosaddegh, who had been warned of the plot, probably by the Communist Tudeh party, rejected the firman and had Nassiri arrested.[63] Mosaddegh argued at his trial after the coup that under the Iranian constitutional monarchy, the Shah had no constitutional right to issue an order for the elected Prime Minister's dismissal without Parliament's consent. However, the constitution at the time did allow for such an action, which Mossadegh considered unfair.[9][64] The action was publicized within Iran by the CIA and in the United States by The New York Times. Mossadegh's supporters (reduced to mainly the Tudeh by this time) took to the streets in violent protests.[7] The Shah, fearing a backlash, escaped from Iran to Iraq and then to Italy by a plane flown by Mohammad Khatam.[65] He was accompanied in his escape by his second wife Soraya Esfandiary-Bakhtiari and Aboul Fath Atabay.[65]
After the first coup attempt failed, General Zahedi, declaring that he was the rightful prime minister of Iran, shuttled between multiple safe houses attempting to avoid arrest. Mossadegh ordered security forces to round up the coup plotters, and dozens were imprisoned. Believing that he had succeeded, and that he was in full control of the government, Mossadegh erred. Assuming that the CIA coup failed, he asked his supporters to return to their homes and to continue with their lives as normal. The Tudeh party members also returned to their homes, no longer carrying out enforcement duties.[7][8][9]
However, General Zahedi, who was still on the run, met with the pro-Shah Ayatollah Mohammad Behbahani and other Shah supporters in secret. There (using CIA money deridingly known as "Behbahani dollars"), they quickly created a new plan. Already, much of the country was in shock from the Shah's flight from Iran, fears of communism, and Mossadegh's arrests of opponents. They capitalized on this sentiment in their plans. The Ayatollah Behbahani also used his influence to rally religious demonstrators against Mossadegh.[7][8][9]
On 19 August, hired infiltrators posing as Tudeh party members began to organize a "communist revolution". They came and encouraged real Tudeh members to join in. Soon, the Tudeh members took to the streets attacking virtually any symbols of capitalism, and looting private businesses and destroying shops. Much of southern Tehran's business district, including the bazaars, were vandalized. With sudden mass public revulsion against this act, the next part of Zahedi's plan came into action. From the vandalized bazaars, a second group of paid infiltrators, this time posing as Shah supporters, organized angry crowds of common Iranians who were terrified about a "communist revolution" and sickened by the violence.[7][8][9]
By the middle of the day, large crowds of regular citizens, armed with improvised weapons, took to the streets in mass demonstrations, and beat back the Tudeh party members. Under Zahedi's authority, the army left its barracks and drove off the communist Tudeh and then stormed all government buildings with the support of demonstrators. Mossadegh fled after a tank fired a single shell into his house, but he later turned himself in to the army's custody. To prevent further bloodshed, he refused a last attempt to organize his supporters.[66] By the end of the day, Zahedi and the army were in control of the government.[7][8][9]
The Shah stayed in Italy until he learned that the coup removed Mossadegh.[62] Allen Dulles, the director of the CIA, flew back with the Shah from Rome to Tehran.[67] Zahedi officially replaced Mosaddegh. Mossadegh was arrested, tried, and originally sentenced to death. But on the Shah's personal orders, his sentence was commuted[8][9][68][69] to three years' solitary confinement in a military prison, followed by house arrest until his death.[70]
https://en.wikipedia.org/wiki/1953_Iranian_coup_d%27%C3%A9tat#Execution_of_Operation_Ajax