Michèle Deslauriers, who's the actual voice of the Montreal Transportation Service which can be heard in the metro, provided the Montreal Teleportation Service's voice in the film. Michele Deslauriers is also Caroline Dhavernas' mother.
Marie-Josée Croze was originally cast as Avril but left the project due to scheduling conflicts. She was the original Avril in the "Mars et Avril" graphic novels by Martin Villeneuve, and was replaced by Caroline Dhavernas in the movie adaptation. Both Croze and Dhavernas were Villeneuve's roommates during his college years.
In January 2014, Mars and April (2012) was sold to the U.S. In February 2016, it was announced that the crew members, for the first time ever in their career, had received a check for a film they made with a deferred pay. An art-house indie film that makes its money back is probably a first in Quebec. This is thanks to the work of the American distributor, but mainly to Martin Villeneuve's TED Talk which attracts lots of viewers to see the film online on platforms such as iTunes and Amazon.
Martin Villeneuve asked the best people in the field to work on his first feature: stage director and actor Robert Lepage (The Far Side of the Moon (2003)), Belgian comic book artist François Schuiten (The Golden Compass (2007), Mr. Nobody (2009)), former ILM Senior Compositor Carlos Monzon (Avatar (2009), Star Trek (2009), Transformers (2007)) and Oscar-nominated Benoît Charest (The Triplets of Belleville (2003)). Because his budget was tiny, Villeneuve worked over a seven-year stretch and offered them the opportunity to dream rather than money.
For his movie, Martin Villeneuve needed seven not-yet-made musical instruments, inspired by women's bodies. Only he had no budget for them. So he got someone else to pay for it - he sold the hypothetical instruments to Cirque du Soleil and got to use them in the movie for free. And he presented an artist friend, Dominique Engel, with a dream project in creating these wildly imaginative props. When Cirque du Soleil CEO Guy Laliberté saw Villeneuve's TED Talk on June 7, 2013, he offered the young filmmaker the "Gravophone" which can be seen in the talk.