Title: Blue Bloods (season 8)
Content:  The eighth season of Blue Bloods, a police procedural drama series created by Robin Green and Mitchell Burgess, premiered on CBS on September 29, 2017. The season contained 22 episodes and concluded on May 11, 2018.
Title: Blue Bloods (TV series)
Content:  in New York City with occasional references to nearby suburbs. The series debuted on September 24, 2010, with episodes airing on Fridays following CSI: NY before being moved to Wednesdays at 10:00 p.m. Eastern and Pacific time and 9:00 p.m. Central and Mountain time for a four-week tryout. After four weeks, it returned to its original Friday 10:00 p.m. Eastern time slot, where it has remained since. In May 2020, CBS renewed the series for an eleventh season, which premiered on December 4, 2020. In April 2021, CBS renewed the series for a twelfth season, which premiered on October 1, 2021.
Title: Blue Bloods (season 8)
Content:  Donnie Wahlberg (Danny Reagan), Bridget Moynahan (Erin Reagan), Will Estes (Jamie Reagan), and Len Cariou (Henry Reagan) are first credited. Sami Gayle (Nicky Reagan-Boyle) is credited next, marking the fourth season she has been included in the opening credits. Tom Selleck (Frank Reagan) receives an "and" billing at the close of the main title sequence. Amy Carlson (Linda Reagan) left between Seasons 7 and 8. Marisa Ramirez, as Danny's partner Detective Maria Baez, and Vanessa Ray, as Jamie's partner Eddie Janko, continue to receive "also starring" billing for season 8. Appearing regularly and receiving "special guest star" billing are Gregory Jbara as Deputy Commissioner of Public Information Garrett Moore, Robert Clohessy as Lt. Sidney Gormley, and Abigail Hawk as Detective Abigail Baker, Frank's primary aide.
Title: Blue Bloods (season 9)
Content:  The ninth season of Blue Bloods, a police procedural drama series created by Robin Green and Mitchell Burgess, premiered on CBS on September 28, 2018. The season concluded on May 10, 2019 and contained 22 episodes.
Title: Blue Bloods (season 7)
Content:  The seventh season of Blue Bloods, a police procedural drama series created by Robin Green and Mitchell Burgess, premiered on CBS on September 23, 2016. The season concluded on May 5, 2017.
Title: Blue Bloods (TV series)
Content:  Selleck mentioned that he was drawn to the project because of the strong pilot script and that he was concerned about becoming involved in an ongoing series because he did not want to compromise his commitment to the Jesse Stone television movies. Beginning January 19, 2011, Blue Bloods was moved to Wednesdays at 10 p.m. for a four-week tryout. In February 2011, the series returned to its Friday night time slot due to the series premiere of Criminal Minds: Suspect Behavior. In the UK, the show helped launch Sky Atlantic by premiering on Tuesday, February 1, 2011, at 10:30 p.m. In Australia, the show premiered in February 2011 in a primetime 
Title: Blue Bloods (season 11)
Content:  The eleventh season of Blue Bloods, a police procedural drama series created by Robin Green and Mitchell Burgess, premiered on CBS on December 4, 2020. Due to production schedules being shortened by the COVID-19 pandemic, the season is reduced to 16 episodes, with the two-hour season finale having aired May 14. On April 15, 2021, CBS renewed Blue Bloods for a twelfth season.
Title: Blue Bloods (season 2)
Content:  The second season of Blue Bloods, a police procedural drama series created by Robin Green and Mitchell Burgess, premiered on CBS on September 23, 2011 and ended May 11, 2012. Ed Zuckerman served as executive producer and showrunner for the season after Green and Burgess departed the show at the end of the first season.
Title: Blue Bloods (season 5)
Content:  The season airs simultaneously on CTV in Canada. In Africa, it began airing on Dstv on October 23, 2014. In the United Kingdom and Ireland, it began on Sky Atlantic on November 5, 2014.
Title: Blue Bloods (TV series)
Content:  In Australia, the series premiered on Network Ten's primary channel on February 2, 2011. Due to poor ratings of the first season, Ten moved the series to its HD channel One, which premiered the second season on October 31, 2011. Due to decreased viewership of Ten's primary channel, season three moved back from August 26, 2013, and season four returned on March 17, 2014. Foxtel channel TV HITS (styled TV H!TS) have started airing the series from Episode 1, weeknights at 8:30pm AEST as of March 20. In New Zealand, the series premiered on TV3 on July 13, 2013. In the United Kingdom and Ireland, Sky Atlantic premiered the series on February 1, 2011, with season two returning on October 4, 2011, season three on December 13, 2012, and season four on November 28, 2013. Season five premiered on January 21, 2015. The series has also been broadcast throughout the Arabic speaking market through MBC Action. Every episode is available to stream on Paramount+.

Question: when does season 8 for blue bloods start?
Answer: September 29, 2017.