This show had it's ups and downs, and in the end was mostly just laughable. But in the first season, when they were still making a sincere effort to be serious, we were treated to this lovely and charming fantasy involving the youngest daughter Penny (Angela Cartwright) and her imaginary playmate who turns out to be all too real. Good story, strong acting, and a good performance from the earlier seasons more menacing Dr. Smith (Jonathan Harris). The story itself would have worked well as an entry in the original Outer Limits, and the concepts around the entity known as Mr. Nobody have been explored in later series, including various episodes of the Star Trek franchise. All in all,an imaginative and satisfying entry in this series, and a standout in sixties sci-fi TV. Highly Recommended.