Q:

Black hole as it is portrayed in the Interstellar film

In the film Interstellar, a character called Cooper travels into a black hole and falls straight into the so-called "tesseract". The tesseract is a 5-dimensional portal in which the ordinary time of 4d spacetime is spatial and can be accessed like an axis on a graph,

Was this scene based on science or fiction?

A:

Yes, the "tesseract" scene was completely fictional.
This movie is notable for its realism in some scenes, due in part to Kip Thorne's involvement as a consultant. In particular, the depiction of the black hole when seen from the outside is accurate in some respects. (See the answers here for details.) The scenes with the wormhole also depict optical effects from the bending of space-time in a realistic manner, though the existence of the wormhole itself is not realistic. New rendering software was developed for those scenes.
However, a major theme of the movie is that physics can't tell us what can be found inside a black hole. In the movie, aliens created the tesseract there so that Cooper could send messages back in time, but that's completely fictional.

