Gerard Depardieu returned to the French stage for the first time in 13 years and said he felt more comfortable there than in movies or on TV. “It’s a different kind of performance. It’s more human, more free. I don’t have my career mapped out,” he told the Paris daily Le Figaro. “I do my job like a blue-collar worker.” In “The Gates of Heaven,” a murder mystery that opened Wednesday at the Theater de Paris, Depardieu plays Charles Quint, a 16th-century emperor who abdicates to seek redemption through religion.