Boston's plush-and-gilt Opera House was rocked to its venerable foundations Monday night as Les Ballets de Paris moved in with a frenzied melange of ballet, can-can, burlesque, and aerobatics. Out of the resulting excitement emerges some of the best entertainment this city has seen in a long time.

The chef-d'oeuvre of the evening in Roland Petit's much-discussed "Carmen." This ballet returns to the sensual, impetuous spirit of the Merimee novel, although its score uses excerpts from Bizet's opera. Rence Jeanmaire is a seductive and fiery Carmen. When she is on the stage the downfall of Don Jose, danced by Petit, becomes completely believable. Jeanmaire and Petit dance together with great smoothness and polish; they are both dancers of the first rank. Serge Perrault and Belinda Wright dance supporting parts with skill.

Confirmed balletomanes of the old school won't like what Petit has the temerity to call another "ballet," a lunatic romp called "L'Oeuf a la Coque." In this explosive and completely delightful work the dancers do handsprings, cartwheels, splits, and double splits--as well as a few bumps and grinds. All this happens when three leggy girls arrive in Hell in the form of chickens. They are danced into ovens by friends dressed as chefs, but soon emerge and proceed to seduce their would-be tormentors. The fiends don't have much of a chance.

Two shorter ballets are also in the program. "Le Combat" is based on a canto of Tasso's "Jerusalem Delivered." In it Collette Marchand, who also stars in "L'Oeuf a la Coque," dances beautifully in a more traditional style. "Le Rendevous" is a somber and moody ballet of Paris which features Henry Danton. As good as they are, these suffer by comparison with such excitingly imaginative spectacles as "Carmen" and "L'Oeuf a la Coque."