Rapper Eminem once again dropped a surprise album, releasing of \u201cMusic to Be Murdered By\u201d on Friday.\r\nThe follow-up to 2018's \u201cKamikaze\u201d - also released without warning - was announced on Twitter just after midnight.\r\nThe Detroit rapper also released a new music video for one of the 20 tracks on the album, \u201cDarkness,\u201d which depicts a shooting at a concert.\r\nThe lyrics and storyline of the video specifically allude to the 2017 mass shooting at a music festival in Las Vegas that left 58 people dead, making it the deadliest mass shooting in modern US history.\r\nIt closes with audio and video footage of news broadcasts from other recent mass shooting around the US and an appeal to register to vote.\r\n\u201cWhen will this end? When enough people care," reads the text at the end of the video. "Register to vote at vote.gov. Make your voice heard and help change gun laws in America.\u201d\r\nA link to the music video on Eminem's website encourages viewers to contact or visit several gun violence prevention organizations, including Everytown for Gun Safety and Sandy Hook Promise.\r\nThe cover art features blood spatter and a bearded Eminem holding both a hatchet and a gun to his head, the latter in apparent homage to Alfred Hitchcock's 1958 album of the same name, Pitchfork noted. \u201cMusic to Be Murdered By\u201d is Eminem's 11th studio album, according to his website.\r\nAmong many collaborators, the album features Ed Sheeran, Skylar Grey, Anderson .Paak and Juice WRLD, the 21-year-old rapper who died in December.