Bad Blood is a song by American singer-songwriter Taylor Swift, from her fifth studio album 1989 (2014). The album and remixed version of the song, with the latter featuring American rapper Kendrick Lamar, was released on May 17, 2015, by Republic Records as 1989 's fourth single. The album version was written by Swift, Max Martin, and Shellback, with Lamar writing his verses on the remixed version. The lyrics of "Bad Blood" describe the betrayal of a close friend. The album version is the eighth track of 1989.
The remixed version received generally positive reviews from music critics, who praised its production and Lamar's guest verses. The song reached number-one in Australia, Canada, Israel, New Zealand, Scotland, and the United States, becoming the third song from 1989 to do so. The accompanying music video was directed by Joseph Kahn and features an ensemble cast. The video previously held the 24-Hour Vevo Record with 20.1 million views, before being surpassed by Adele's "Hello". It won Video of the Year and Best Collaboration at the 2015 MTV Video Music Awards. The song and its music video were nominated for Best Pop Duo/Group Performance and Best Music Video at the 58th Grammy Awards.
A cover version of "Bad Blood" was released as the first promotional single from singer-songwriter Ryan Adams' interpretation of Swift's 1989 album, released in September 2015.
"Bad Blood" first charted on the U.S. Billboard Hot 100 for two weeks in November 2014 and January 2015 as an album cut from 1989, peaking at number 78. Following the music video premiere at the 2015 Billboard Music Awards, the remixed version of the song featuring Kendrick Lamar re-entered the chart at number 53 and number 26 on the Digital Songs Chart, selling 47,000 digital copies. The following week, the song topped the Billboard Hot 100 on the week ending May 24, 2015, selling 385,000 copies and jumping 52 positions, one of the largest jumps to the top spot in Billboard history. It became her fourth number one single and the third number one from 1989 (following "Shake It Off" and "Blank Space"), making Swift the first artist since Adele to yield three Hot 100 chart toppers from the same album; it is also her fourth consecutive top-10 single from 1989. It also became her 18th top 10 single and Lamar's second (also his first number-one single in the United States). It held the top spot for one week, before being replaced by Wiz Khalifa and Charlie Puth's "See You Again". As of July 2015, the song has sold 2,210,000 digital copies in the U.S.
"Bad Blood" received generally mixed reviews from music critics. The song was mostly criticised for its writing, with many reviewers[who?] describing it as full of clichés."Mix her uncharacteristically bratty tone with the weakest beat and the softest cliches, this labor clunks to the finish line. Grade: C-" The chorus in particular was criticised with Jim Farber of The New York Daily News describing it as a "repetitive, arena-mongering chant". The song was also criticised[by whom?] for its weak production. However, Entertainment Weekly listed it as one of the best songs on the album.
However, the remixed version of the song received mostly positive reviews, with praise[from whom?] directed at Lamar's guest verses and the reworked instrumental. George Seabrook of The Edge awarded the song four and half stars out of five, and called it "glorious" and "intoxicating". He praised the song for "Lamar’s simple, brutally effective verses" and acknowledged the collaboration as "not just one more meaningless stunt collaboration, but a powerful new duo".