In general, this action drama does a good job of establishing its atmosphere, but otherwise most of the movie doesn't really work very well. It has too many slow stretches, and it doesn't make use of many of the possibilities in its characters and setup.
Rose Hobart and Charles Bickford star as an estranged couple, with the wife traveling deep into the wilds to find her husband, creating a delicate and dangerous situation between them and the native ruler whom the husband now serves as a court physician. The situation had lots of potential, but much of the middle part of the movie simply uses up screen time rehashing the same ground. The loyal servant girl played by Lupita Tovar also offered some possibilities, but she is never used for anything more than fetching things.
The finale is full of action, but it would have worked much better if it had come after a more careful buildup. The movie does establish the jungle atmosphere quickly and believably, with a lot of wild animals and other details, and for a while the setting is interesting enough to keep your attention even when not a lot of significance happens. Eventually, though, the story just bogs down, and doesn't go much farther until just before the finale. Overall, "East of Borneo" is probably more significant as the source of material for Joseph Cornell's interesting experimental feature "Rose Hobart" than it is in its own right.
