The guest artist at the Mercury — The Orchestra Redefined's 8 Seasons concert has a familiar name: Plante. Mercury's Antoine Plante is conducting the orchestra as they perform a combination of classical composer Antonio Vivaldi's Four Seasons and tango master Astor Piazzoll's Four Seasons of Buenos Aires. Plante's brother, Denis Plante, performs on bandoneon (a small accordion-like instrument used in tango). ''The idea is to put these two Seasons up against each other. We're taking Vivaldi's Four Seasons, which is very dynamic and really shows Vivaldi at his best. Then we put on top of that Piazzoll's Four Seasons of Buenos Aires. These pieces were written 250 years later, and they have a definite tango feel. Luckily, we have a chance to work with one of the best bandoneon players in the world…who just happens to be my older brother,'' Plante says. ''It's a very audience-friendly show with the great energy from Vivaldi and then the passion of Piazzoll.''