This is one of two episodes that has Diana Muldaur, the actress that would play Dr. Pulaski for The Next Generation twenty years later. She happens to play a the female doctor that contains the love interest of the two disembodied spirits. One of the better episodes of the show, it still contains many of the irregularities that plagued the original. Dr Ann would only appear in one other episode despite her apparent importance to the ship at that moment. Also it seems unlikely that super intelligent beings wouldn't be able to create an android that would not be able to "feel" in the loose physical sense of the word. Also for some reason Dr McCoy becomes does not suspect anything is amiss although he is always the most paranoid character. Still a fun 60s SciFi memory.
Review of Return to Tomorrow
