The Beastie Boys [ tickets ] continue to add shows to their ongoing North American tour, despite an announcement detailing the "final" dates of the trek just days ago.

The hip-hop trio has added a Sept. 20 show in Montreal to the calendar, along with a Sept. 24 Detroit date and a second, instrumental-only Toronto show to accompany the group's previously announced Sept. 21 show in the Canadian city. Additional instrumental shows in Montreal and Detroit are "expected shortly," according to the Boys' publicist.

The group resumes the August leg of its tour Thursday (8/16) in the Denver area. The Boys will also play an instrumental-only Aug. 17 show in Denver, continuing the group's recent trend of scheduling two shows in each metropolitan area that the band visits, one show an all-instrumental affair showcasing the songs on the band's latest album, "The Mix-Up," and the other show a traditional hip-hop affair.

"The Mix-Up" is the Beastie Boys' first studio album since 2004's "To the 5 Boroughs," which itself emerged after a six-year gap following 1998's "Hello Nasty." The new album is the group's first instrumental-only effort since the 1996 compilation "The In Sound from Way Out."

All three Boys play instruments on the new album, which is supplemented by contributions from longtime collaborator Mark Ramos-Nishita, also known as Money Mark.

Snippets of songs from the new set can be heard streaming at the group's website, which also includes behind-the-scenes videos of the recording sessions for "The Mix-Up."