“Tosca” began its season run at the Metropolitan Opera on Saturday evening with an unexpected cast change, a major debut, and a veterans returning in a signature role. The three principals together mounted a colorful, if a bit gritty, performance.

Singing the title role was soprano Maria Guleghina, substituting on short notice for the troubled Andrea Gruber, who was ill. Ms. Guleghina had the role two seasons ago, and I wrote at the time in these pages that her acting ability was superb even as her vocalizing was somewhat haphazard.

Saturday night she wore the tiara, pendant earrings, and necklace originally designed for Maria Callas, and now housed by Swarovski. Although Callas and Ms. Guleghina are very different singers, there are two points of comparison that help define the latter. First, like La Divina, she is an actress of astounding ability. Contemporary audiences at the premiere of Tosca would have remembered the performance of Sarah Bernhardt in the play by Victorien Sardou. Critics said that her laying out of the body of Scarpia was both frightening and holy. This current player has taken the measure of this role, elevating the art of opera acting — not, after all, known for its subtleties — to new heights in this devastatingly intimate performance.

Even the most ardent of her fans — and I am one of them — admit that Maria Callas did not have a conventionally pretty voice. Her secret was what she did with what she had. Ms. Guleghina is also in this category, although with a very different type of voice. Her instrument is powerful and solid, adept and accurate, but not usually described as beautiful. However, on this night she came close, her “Vissi d’arte” not only moving but lovely as well.

Making his debut in the role of Cavaradossi was Argentinian tenor Jose Cura. When I heard him two years ago as Samson in the Saint-Saens, I was disturbed by his bellowing, but this evening he was actually quite good — he maintained a smooth lyrical line while intoning at an impressively high volume level. And he was a natural partner for Ms. Guleghina, who is also a champion projector. Their “Non la sospiri la nostra casetta” has to be one of the loudest ever, but neither sacrificed any intonation for this house-filling sound. Mr. Cura’s “E lucevan le stelle,” his character’s last big number and one of Puccini’s most poignant compositions, was really very moving.

James Morris returned as Baron Scarpia — a little raspy, but somehow his growl was just perfect for this naturalistic trio of singers. All three were a little grainy in their respective throats, but this only ornamented an altogether earthy performance — a little like an Anna Magnani movie. Mr. Morris is also a fine actor and his scene with Ms. Guleghina was a perfectly choreographed murder. There were some initial coordination issues between the substitute soprano and the conductor, but no worries of blocking. She always knew where to hit her marks.

The rest of the cast was fine. Paul Plishka once again resumed the role of the Sacristan. Mr. Plishka is a wonderful character actor who can still make his presence known. Bernard Fitch was a suitably reptilian Spoletta, and my favorite music in all of Puccini was admirably realized offstage by Deena Sydney Fink as the shepherd boy.

The story of the night, though, may well have been in the orchestra pit with the excellent leadership of debut conductor Nicola Luisotti, who grabbed our attention from the first notes and kept up an intensity rare for a non-Levine performance at the Met. Having three such prodigious singers allowed him to let loose the forces of his magnificent instrumental ensemble without worrying about drowning out the stars. He made the most of his opportunity.

This was performance number 881 of “Tosca” at the Met. Maybe this wasn’t the most beautiful “Tosca” in memory, but it may have been the most memorable for quite some time.

Until December 2 (Lincoln Center, 212-721-6500).