Maynard James Keenan (born James Herbert Keenan; April 17, 1964), also known by fans simply by his initials as MJK, is an American progressive metal singer, songwriter, musician, record producer, winemaker, and actor, best known as the vocalist for Grammy Award-winning American progressive metal band Tool. He is originally from Ohio, but spent his high school and college years in Michigan. After serving in the Army in the early 1980s, he attended Kendall College of Art and Design in Grand Rapids. He moved to Los Angeles, California in 1988 to pursue a career in interior design and set construction. Shortly thereafter, he formed the band Tool with Adam Jones.
Keenan is known as the lead singer of the multi-platinum rock bands Tool and A Perfect Circle. He has released four studio albums with Tool, and three with A Perfect Circle. In 2003, he created Puscifer as a side project and has subsequently released two studio albums. Since rising to fame, Keenan has been noted as being a recluse; however, he does emerge to support charitable causes.
In addition to his music career, he has performed improvisational stand-up comedy and ventured into acting. He currently owns Merkin Vineyards and the associated winery, Caduceus Cellars, and also partly owns Stronghold Vineyards, all of which are located in Arizona, where he lives. Among other business ventures, he is a partner in the Los Angeles restaurant Cobras & Matadors, and also owns an organic produce market in Cornville, Arizona, which features a food court and a tasting room for his wines.