Lost in Space (movie)

Ok this movie is pretty much a steaming pile, but I was mildly entertained.. Until future Dr. Smith shows up as the embodiment of evil as a giant cockroach.

I have huge problems with this because Smith was a wily guy in the original show, but hardly so evil as the portray him in the movie. But my real problem is a logistical one.

The transformation was caused by a bite he received early in the film from some kind of space-spider. But when the movie ends, he is still alive and still being held as a captive by the Robinsons... do they kill him right after the credits start rolling or did Dr. Robinson simply forget? Won't he still become the monster? They simply never resolve this huge plot point.