<P> NCIS was originally referred to as Navy NCIS during season one ; `` Navy '' was later dropped from the title as it was redundant ( the `` N '' in `` NCIS '' stands for `` Naval '' ) . In season six , a two - part episode led to a spin - off series , NCIS : Los Angeles . A two - part episode during the eleventh season led to a second spin - off series , NCIS : New Orleans . While initially slow in the ratings , barely cracking the Top 30 in the first four seasons , by its sixth season , it became a top five hit , and has remained there since . In 2011 , NCIS was voted America 's favorite television show in an online Harris Poll . The series finished its tenth season as the most - watched television series in the U.S. during the 2012 -- 13 TV season . On February 29 , 2016 , NCIS was renewed for its fourteenth and fifteenth seasons . The fifteenth season premiered on Tuesday September 26 , 2017 . Maria Bello will join the cast as a series regular from episode four , replacing outgoing series regular Jennifer Esposito . </P>
<P> NCIS was originally referred to as Navy NCIS during season one ; `` Navy '' was later dropped from the title as it was redundant ( the `` N '' in `` NCIS '' stands for `` Naval '' ) . In season six , a two - part episode led to a spin - off series , NCIS : Los Angeles . A two - part episode during the eleventh season led to a second spin - off series , NCIS : New Orleans . While initially slow in the ratings , barely cracking the Top 30 in the first four seasons , by its sixth season , it became a top five hit , and has remained there since . In 2011 , NCIS was voted America 's favorite television show in an online Harris Poll . The series finished its tenth season as the most - watched television series in the U.S. during the 2012 -- 13 TV season . On February 29 , 2016 , NCIS was renewed for its fourteenth and fifteenth seasons . The fifteenth season premiered on Tuesday September 26 , 2017 . Maria Bello will join the cast as a series regular from episode four , replacing outgoing series regular Jennifer Esposito . </P>
when did the new season of ncis start
when did the new season of ncis start
Tuesday September 26 , 2017
Tuesday September 26 , 2017