Lady Gaga performed an iconic French cabaret classic at the Paris Olympics opening ceremony on Friday.
The appearance of the pop star was kept under tight wraps by organisers, but rumours that she might perform spread after she was spotted in the French capital.
The opening ceremony began with the depiction of a fictional scenario in which the arrival of the Olympic flame goes awry, ahead of an extravagant show on the river Seine.
French football superstar Zinedine Zidane was shown running across Paris to bring the flame, in a pre-recorded video that included him taking it onto the metro.
The ceremony features a fleet of barges taking nearly 7,000 athletes on the river, by some of Paris' most famous landmarks.
For the first time in Olympic history, the opening ceremony is taking place outside the main stadium, with some 300,000 people watching in person from specially built stands, on the river banks, and another 200,000 from overlooking balconies and apartments.
A giant plume of blue, white and red smoke was sent high above a bridge over the river as the ceremony started.
Some 45,000 police and thousands of soldiers have been deployed in a huge security operation in Paris for the opening show. Armed police patrolled along the river in inflatable boats as the armada made its passage along the Seine.
More than 10,500 athletes will compete at the Olympics, 100 years since Paris last staged the Games.
Competition started on Wednesday and the first of the 329 gold medals will be awarded on Saturday. The closing ceremony will take place on August 11.