The first season of "Wonder Woman" was set during World War II. When the series moved from ABC to CBS the next year, the entire format of the show was changed with the immortal Wonder Woman returning to civilization in the late 1970s and teaming up with the son of Steve Trevor from the first season (of course played by the same actor). Lynda Carter's costume also underwent some minor modifications with the changeover.
The Flintstones was the first animated series made for prime-time network television. It was broadcast from September 30, 1960 to April 1, 1966 on ABC and was the most financially successful network animated franchise for nearly three decades, until it was finally overtaken by The Simpsons.
NBC executives supported Hill Street Blues in its infancy despite a lack of viewers, and in 1981 it became the lowest-rated series ever renewed for a second season. It was only renewed for ten episodes, however, and wasn't picked up for the full season until ratings improved.