Time Out says
Friendly warning! We're working hard to be accurate. But these are unusual times, so please check that venues remain open.
Whether you're broke, or just fancy letting serendipty decide which show you'll see, the Kiosque Théâtre is a half-price ticket office for same-day performances in comedy, stand-up, cabaret and highbrow theatre. The main Kiosque is at Madeleine (opposite n° 15 place de la Madeleine), but you'll also find stands at Ternes (middle of the square by the Métro exit) and Montparnasse, in front of the station.