R2-D2 and C-3PO were in every Star Wars movie, including the sequels, yet Darth Vader and Ben Kenobi don't seem to recognize them in the original.
One of the odd things about the Star Wars prequels is that they left quite a few holes in the plot that don't quite fit.
The fact that Ben Kenobi has no reaction when he first sees them is one of those plot holes. In fact, he makes it a point of saying "I don't recall ever owning any droids.", even though they spent a great of time together in all 3 sequels.
Not only did the two droids appear in the prequels, but they reveal that young Anakin Skywalker / Darth Vader actually BUILT C-3PO himself.
They try to fix the plot holes a little bit by ordering the droids memories to be erased at the end of Episode III, but only expl... [More]
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