Speaking of bright lights: Back in 2015, five penthouse units on the top six floors of The Charles, a 32-story luxury condo tower at 1355 First Ave., were sold to two unidentified but “related” families for a combined $58.6 million.

They planned to convert the five merely large units into two ginormous ones.

There’s been no news since. But some sleepless neighbors in the East 70s would like to know why the six highest floors are, each night, lit up inside as bright as the Empire State Building’s top.

The blinding illumination from behind curtain-less windows reveals furniture, chandeliers and other details. But is anybody home?

Reps for tower developer BlueRock noted that the residences are now privately owned and said they didn’t know why they’re lit.