Sweaty bodies grunting during tennis. Then more of the same away from the court in cheap motels and student rooms. “Challengers” is the story of how a love triangle plays out on the tennis court, in a stylish and steamy film directed by Luca Guadagnino, who many will recall made “Call Me by Your Name.” Starring Zendaya and Josh O’Connor, “Challengers” is more than just an erotic film. Guadagnino has created a highly entertaining work packed with suspense that explores desire, power and control on multiple levels. The film centres on tennis pro played by Zendaya, who is becoming one of the most…