Without – for the most part – the two best characters from II (Spock and Khan), this is a fairly unremarkable, mediocre necessary link to IV – except maybe the last 10 minutes, which are all that’s needed. And even then only as a warmup to IV if you want one.
The other cast members have to act more to compensate for no Spock, which isn’t so good as they invariably overreach themselves.
Tribbles good, dog putting up with Klingons bad.
Grade: D