A cult American death metal unit based out of Tampa, Florida, Nocturnus emerged in the late 1980s and quickly became known for their cutting-edge, science fiction-inspired lyrics and punishing style that incorporated elements of keyboard-driven progressive metal. In 1999, after issuing a trio of influential extreme metal albums, the band ceased operations but re-formed in 2015 under the moniker Nocturnus AD.

The group was founded in 1987 by ex-Morbid Angel singer/drummer Mike Browning, guitarists Mike Davis and Gino Marino, bassist Jeff Estes, and keyboardist Louis Panzer. Following the demo Science of Horror, the group swapped Marino for guitarist Sean McNenney prior to recording its 1991 Earache label debut The Key. Vocalist Dan Izzo signed on for 1992's Thresholds, which also saw bassist Chris Anderson substituting for Estes; Anderson himself was replaced by bassist Emo Mowery for Nocturnus' third album, a self-titled 1993 release for the Moribund label -- the record was also the first without Browning, who turned over his drumming duties to James Marcinek. The group soon dissolved, re-forming in 1999 around a roster of Davis, McNenney, Panzer, Mowery, and drummer Rick Bazzaro to record the comeback effort Ethereal Tomb, which was released via Season of Mist. The band called it quits again in 2002 but managed to issue a collection of unreleased material (The Nocturnus Demos) and a concert LP (Farewell to Planet Earth) in 2004.

In 2015 Browning, who had formed the band After Death upon leaving Nocturnus, began playing shows under the moniker Nocturnus AD with his After Death bandmates filling out the rest of the roster. Paradox, the group's fourth full-length effort and first outing under the augmented name, was released in 2019. ~ James Christopher Monger, Rovi