Ripplin’s review published on Letterboxd :
An Earth ship looking for other inhabitable planets comes across a ship that went missing during its own research mission 20 years prior, perched near the entrance to a black hole.
This one definitely has strong shades of 20,000 Leagues Under the Sea, with Captain Reinhardt (Maximilian Schell) in a role parallel to that of Captain Nemo, an eccentric figure with a god complex in command of a massive ship called the Cygnus, making all the rules and playing host to unwanted guests. The guests in question include Anthony Perkins, Ernest Borgnine, Yvette Mimieux, Robert Forster, Joseph Bottoms and two robots called V.I.N.C.E.N.T (who has some great philosophical quotes) and B.O.B. They gradually find out some terrible truths aboard the Cygnus...
This is a really beautiful film. It has lots of interesting and elegant ship/interior/robot designs, some of the best matte paintings you'll ever see, and, though dated in places, many of the effects shots hold up very well, including lasers that look better than in Star Wars much of the time and some very impressive miniature work. It's a film that all who worked on it can be proud of.
The story plays out a little controversially. It was Disney's first PG-rated movie, and it definitely earned it, partially because of language, partially because of violence, including a death scene that, while nothing is actually shown, is pretty graphic in its own way. But beyond that, the ending was sort of a non-ending that was filmed very late into production. It does feel tacked on. Having watched this again, I do have my own theories, and it's satisfying enough for me, but it definitely could benefit from something more solid.
Overall, an enjoyable experience and a sight to behold! I will postulate my ending theory in a comment below.
P.S. I watched this shortly after I got a copy of the soundtrack, which I've posted in my vinyl blog. Check it out!