FILE - In this Thursday, Jan. 26, 2011 file photo, made available by London's Royal Opera House, Ukrainian dancer Sergei Polunin dances in the Royal Ballet production of Sleeping Beauty by Tchaikovsky in 2011 at the Royal Opera House, London. Sergei Polunin, the ballet superstar as famous for his abrupt exits as his athletic leaps, is returning to the London stage. And this time, he's going to show up and stay the course. Almost certainly. Polunin said Tuesday, May 28, 2013: "You have to take it day by day, but I'm pretty sure." Polunin went from dance-world celebrity to headline news when he walked out last year on the Royal Ballet, which had made the Ukrainian prodigy its youngest-ever male principal dancer at 19. AP Photo/ Johan Persson /Royal Opera House, File LONDON (AP) - Sergei Polunin, the ballet superstar as famous for his abrupt exits as his athletic leaps, is returning to the London stage in a production of "Coppelia" at the home of the English National Ballet. "You have to take it day by day, but I'm pretty sure," said Polunin, who made news headlines when he walked out last year on the Royal Ballet, which had made the Ukrainian prodigy its youngest-ever male principal dancer. Last month he did it again, quitting the ballet "Midnight Express" days before it was due to open in London. "You take it day by day, but you mature as a dancer," 23-year-old Polunin said Tuesday at the announcement of the London performances by his new company, Moscow's Stanislavsky Ballet. After he quit the Royal Ballet, Polunin - who had moved to Britain aged 13 to study dance - said he walked out because he could no longer handle the stress of a dance career. There were rumors of hard partying by the dancer, who lived for a time above a tattoo parlor he co-owned on a gritty London street. Months later he reappeared in Moscow, becoming a celebrity in ballet-loving Russia by winning a televised competition - a sort of "X Factor" for classical dancers. He has since danced with the Stanislavsky and other companies, including the Royal Ballet. That hasn't erased his reputation - at least in Britain - as the bad boy of ballet. "In Russia, it's not like that," said Stanislavsky general director Vladimir Urin. I don't understand why he was called that in London. He's a good boy. Polunin certainly looked healthy, calm and collected Tuesday, in jeans and a black leather jacket, talking about how he relished the "huge technical challenge" of Leo Delibes' French comic ballet. He will dance the lead role of Frantz in three of six performances of "Coppelia," which begin July 11 at the London Coliseum. The shows feature a roster of the Stanislavsky's young talent in a version of the work created in 1975 by the late choreographer Roland Petit. "It's like you take your body to the next level in this ballet," Polunin said. And the acting is very free. Normally I don't like happy ballets, but this one has a French sort of humor. He apologized to London audiences for having let them down, saying he quit "Midnight Express" because of "a health reason." In explanation of his erratic behavior, he said he was "like all young people - you try to find yourself in life." He has mended fences sufficiently with "Midnight Express" director Peter Schaufuss - who had publicly berated Polunin for leaving him in the lurch - for Schaufuss to be involved with the upcoming London shows. Schaufuss said Polunin had a "special quality" that only comes along in a dancer once a decade or so - "that special little thing which separates the good ones from the great ones." Polunin's presence has helped the Stanislavsky attract large audiences, and the company has escaped the controversy swirling around the rival Bolshoi, which is facing allegations of corruption and mismanagement, as well as an acid attack on its artistic director. After a tumultuous year, Polunin said he is in a more stable place now, artistically and personally. "In Russia it's great because you can concentrate 100 percent on your work," Polunin said. There are not as many distractions as London or in the West.