Gremlins 2: The New Batch (1990)

Directed by Joe Dante, Gremlins 2: The New Batch reunites Zach Galligan and Phoebe Cates as Billy and Kate, now working in a high-tech Manhattan skyscraper where Gizmo once again gives rise to a new generation of Gremlins. As the creatures multiply and mutate into increasingly bizarre forms, the building descends into chaos. The sequel pushes the original film’s creature horror further into comedy, parody and exaggerated monster mayhem.

Från IMDB:
The Gremlins are back, and this time, they've taken control of a New York City media mogul's high-tech skyscraper.