Alexzandra Spencer Johnson (born November 4, 1986) is a Canadian musician, film, television, voice actress, and philanthropist. Her debut album Voodoo was independently released with her brother Brendan Johnson in 2010, followed by the demo release of The Basement Recordings in 2011, with its sequel, The Basement Recordings II, and EP Skipping Stone in 2012. The Basement Recordings III was released in 2013. A follow-up extended play Heart followed in 2014; with her sophomore effort Let 'Em Eat Cake being released October of that year. Johnson's third studio album A Stranger Time was released in 2017 and her fourth, Still Alive, in 2020. Johnson's fifth album is to be titled Seasons, she allowed her fans to vote for the title via her personal Patreon. An official release date has yet to be announced but she begun announcing dates for an intimate Europe/ US Tour set to begin in the early spring of 2023 to promote its release.

She is best known for her roles as Jude Harrison in the CTV series Instant Star, as Annie Thelen in the Disney Channel series So Weird, and as Erin Ulmer in the 2006 horror film Final Destination 3. Johnson made history as the first actress to play the iconic superheroine Saturn Girl from DC Comics popular graphic novels in the T.V. series Smallville. She was nominated three times for a Gemini Award for Best Performance in a Children's or Youth Program or Series (Instant Star), winning the award in 2008.