Maureen Montgomery has 4 Theory of a Deadman concerts.

Theory of a Deadman (or Theory for short) is a rock band from North Delta, British Columbia, Canada, formed in 2001, signed by Nickelback vocalist Chad Kroeger to 604 Records, after lead singer Tyler Connolly gave Kroeger a demo tape. The band also includes traits of other music styles, such as country, metal and more acoustic elements. Theory has released six studio albums and three #1 hits on the Mainstream Rock Chart. The band scored the entire soundtrack for the video game, "Indigo Prophecy" / "Fahrenheit".