Improbus Atrum are a Maltese melodic black metal band, founded by Ayrton Tonna (guitars; also of Thy Legion) and Jean Paul Vella (bass).

Biography
Improbus Atrum was formed in May 2006 by Ayrton Tonna and Jean Paul Vella with a desire to play black metal. Later Alesio Torrisi (drums), Keith Farrugia (vocals) and Keith Muscat (keyboards) joined the band. There were subsequently several line-up changes due to personal reasons. Later in 2007 Improbus Atrum recorded their first demo Bearing the Mark. Vella had to leave the band to go to England, and Micheal Zbubi joined the band. The name Improbus Atrum means "perverse dark" in Latin.

Line-up
Current members
* Leviathan (ex Martyrium) - vocals
* Ayrton Tonna - guitars
* Alessio Torisi - drums
* Keith Muscat - keyboards
* Kurt Dimech - bass


Former members
* Jean Vella - bass

Discography
* Bearing the Mark demo (2007)