I took one of these trains. The service was short-lived though.
It was called iDNight, by iDTGV, a former low cost high speed train operator in France. The idea was to run high speed trains at a slow speed during the night, turning a 3 hour trip into an 8 hour trip so that you can get a full night, and also so it can leave as the departure station is closing and arrive as the destination station is opening, therefore exploiting downtime, I guess.
These were not sleeper cars but regular high-speed train cars, not ideal for sleeping, but since most seats were vacant, at least in my experience, you could easily get two seats for yourself.
It was called iDNight, by iDTGV, a former low cost high speed train operator in France. The idea was to run high speed trains at a slow speed during the night, turning a 3 hour trip into an 8 hour trip so that you can get a full night, and also so it can leave as the departure station is closing and arrive as the destination station is opening, therefore exploiting downtime, I guess.
These were not sleeper cars but regular high-speed train cars, not ideal for sleeping, but since most seats were vacant, at least in my experience, you could easily get two seats for yourself.