The London Underground could again grind to a halt in August after the RMT union said its members would join Aslef and Unite on the picket line over Boris Johnson's Night Tube plans.
The walkout would take place from 6.30pm on Wednesday 5 August to Thursday 6 August, while strike times for driver members will run slightly later, between 9pm to 8.59pm.
RMT said it was striking over an overtime ban, which it claimed had "already severely impacted on staff availability to run services".
General Secretary Mick Cash said workers should be allowed a better work/life balance.
"The unity and determination of staff across London Underground in the dispute over the Night Tube, the imposition of the rosters from hell and the destruction of any semblance of work/life balance remains rock solid," he said.
"Workers in all grades are furious at the attempt to rip up long-standing agreements in an effort to bulldoze through these wholly unacceptable new working patterns.
"RMT also remains in dispute over the parallel issue of the axing of 850 station staff jobs, cuts that make a mockery of the safe delivery of the Night Tube in just a few weeks time.
"RMT remains available for talks and tube managers need to understand the universal anger of their staff if we are to start making some serious progress in negotiations."