AdvertisementKendrick Lamar Fires A Warning Shot With New Song 'The Heart Part 4'March 24, 2017Rodney CarmichaelfacebookEmailKendrick Lamar performs in Brooklyn in December 2016. On Thursday night, Lamar released a new song, "The Heart Part 4," that seems to preview a new album by Lamar, to be released on April 7. (Getty Images for American Express)