<P> Actors who left the cast include Ryan Donowho (Johnny), Jeri Ryan (Charlotte), Shaun Duke (Henry Griffin), Kayla Ewell (Casey), and Nikki Reed (Sadie). New members who joined the cast include Kevin Sorbo as Ryan's father Frank; Gary Grubbs as an oil merchant who calls himself The Bullit; Brandon Quinn as Bullit's son Spencer; Chris Pratt as an environmental activist nicknamed Che; and Wayne Dalglish and Corey Price as Luke Ward's younger twin brothers Brad and Eric . New guest stars who joined in recurring roles include Tia Carrere as Dean Torres, singer Chris Brown as lonely band geek Will Tutt, Henri Lubatti as Taylor's ex-husband Henri - Michel de Momourant, and Steve - O in a cameo role as an unnamed marine . </P> <P> While ratings were lower than those of the third season, the final season is generally regarded by fans and critics as an improvement on the third . Variety's Josef Adalian said that "(the show) is once again in great creative shape". He added that "the scripts are snappy, the plots make sense, the acting's solid, (and) the music is appropriately indie" but criticized Fox for "throwing away" the show by giving it the Thursday 9: 00 p.m. timeslot . The difficult timeslot Adalian was referring to was against two other very popular shows, CSI and Grey's Anatomy . With a later start to the season in November the premiere attracted 3.4 million viewers, which was a series low and marked a 55 percent decrease in the 18--49 demographic, from the third season premiere . The first half of the season averaged 4.06 million viewers, with the season as a whole averaging 4.6 million viewers . This increase was mostly due to 6.7 million viewers, 76 percent more than the season average, tuning in to see the final ever installment of The O.C. </P> <P> Due to a combination of low ratings and the death of Marissa in season three, it was rumored that the show would not return for a fifth season . In June 2006, Fox confirmed that "the current order for The O.C. is 16 episodes", but added that there was a chance to add more installments . In September 2006, Rachel Bilson said that she felt "like the show is over", and co-star Kelly Rowan stated that many of the cast realized the show was close to being cancelled . Rowan said that "when (the fourth season) was picked up for just 16 episodes this year the cast had a feeling the end was near". On January 3, 2007, Fox announced that The O.C. was to be cancelled . In a statement, Schwartz said "This feels like the best time to bring the show to its close" adding that "what better time to go out than creatively on top". A campaign was launched to save the show and over half a million people signed an official petition at www.fox.com/oc/savetheoc . There were rumors that the show would be saved, and a move to the CW Television Network was mooted; however, CW president Dawn Ostroff, whose company is partly owned by Warner Bros, confirmed in January 2007 that while the move was discussed, it was decided against . </P> <P> Schwartz said that the cancellation of the show "was really creatively liberating, not worrying about ratings ." Belinda Acosta of The Austin Chronicle agreed praising the show's "new energy" and its ability to successfully cover "the transition between high school and college that other series have stumbled over". Entertainment Weekly's Ken Tucker commented that the fourth season was "a succession of terrific subplots" and praised new main cast member Taylor "as a fine, funny love interest for Ryan". Greg Elwell of DVD Talk described Bullit as "the breakout character of the season" but commented that the seasons "dark opening (...) didn't do much to keep viewers around". IGN's Eric Goldman was also critical saying that "as amusing as Che was, his inclusion into some later episodes gets a bit tired". Goldman also commented that "the second half of Season 4 wasn't quite as solid as the first (half)"; however, he added that while the fourth season had to prove itself again as an enjoyable watch "Josh Schwartz rose to this challenge (...) once again creating a show that was witty and self - aware". </P>

Why is there only 4 seasons of the oc
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