MUSIC

THE BEST OF BOTH WORLDS R&B star Mary J. Blige and rapper Jay-Z — whose classic duet “Can’t Knock the Hustle” is nonpareil in the hip-hop canon — co-headline the Heart of the City tour at Madison Square Garden. The Brooklyn-born hip-hop mogul and the Yonkers-bred songstress both released albums in the last quarter of 2007. Jay-Z’s “American Gangster” features songs inspired by the film of the same name, and Ms. Blige’s “Growing Pains” boasts the hit single “Just Fine.” Concertgoers can expect performances of some of the artists’ best-known hits, from Ms. Blige’s debut single “Real Love” to Jay-Z’s “Izzo (H.O.V.A.)” and “Big Pimpin’.” Tomorrow, 7:30 p.m., Madison Square Garden, 4 Pennsylvania Plaza, 32nd Street at Seventh Avenue, 212-307-7171, $69.75–$199.75.

OPERA

FRESH COMPOSITIONS New York City Opera presents “VOX 2008: Showcasing American Composers.” Among the highlights is David Little’s “Soldier Songs,” based on interviews Mr. Little conducted with military personnel, and Scott Davenport Richards’s jazz opera “Charlie Crosses the Nation,” about a biracial jazz musician making a living during the big-band era. The VOX committee selects up to 12 operas (either finished or in progress) by emerging and established composers to stage with full orchestration and professional casts. The program is now in its ninth season. Pre-concert discussions begin at noon. Saturday–Sunday, 2–5:30 p.m., New York University, Skirball Center for the Performing Arts, 566 LaGuardia Place at Washington Square Park South, reserve tickets at vox-nyco.com, free.

READINGS

AN AFTERNOON WITH BARBARA Veteran broadcaster Barbara Walters reads from and signs copies of her memoir “Audition” (Knopf ), in which she recounts her colorful and glamorous life in television journalism. The pioneering Ms. Walters spent more than two decades as chief correspondent and co-host of ABC News’s primetime newsmagazine program, “20/20,” before striking daytime television gold with an all-female chat-fest, “The View.” In 1976, Ms. Walters made television history as the first woman to co-anchor an evening news program, alongside a less-than-delighted Harry Reasoner. Tomorrow, 12:30 p.m., Barnes & Noble, Lincoln Triangle, 1972 Broadway at 66th Street, 212-595-6859, free.

GALLIC SURPRISE The author of “Dawn Dusk or Night: A Year With Nicolas Sarkozy” (Knopf ), Yasmina Reza, discusses what she discovered about the French president in 2006–07, when she was given near-unfettered access to him on the campaign trail. An award-winning playwright, Ms. Reza presents a candid portrait of Mr. Sarkozy’s quest for power, venturing beyond the details of his love life that have grabbed headlines of late. Tonight, 7 p.m., Strand Bookstore, 828 Broadway at 12th Street, 212-473-1452, free.

TALKS FANCY-FREE The New York City Ballet, which opened its spring season last week and features a Jerome Robbins celebration, hosts a conversation with the author of “Somewhere: The Life of Jerome Robbins” (Random House), Amanda Vaill. Ms. Vaill reflects on the career of Robbins, one of the great choreographers of the 20th century, who crafted dances for the ballet and Broadway stage. Audience members are treated to rare footage of Robbins in rehearsal with many of New York City Ballet’s principal dancers. Tonight, New York State Theater, West 63rd Street at Columbus Avenue, 212-870-5570, $5.

DARWIN REWARDS “Darwin: Yesterday and Today” is the subject of a discussion hosted by the American Museum of Natural History and the New York Botanical Garden. Panelists revisit the early response to Charles Darwin’s work, including “On the Origin of Species by Means of Natural Selection” (1859). The speakers are a Darwin historian, David Kohn, a philosopher, Michael Ruse, and an environmental microbiologist, Rita Colwell.

Tomorrow, 5 p.m., New York Botanical Garden, Arthur and Janet Ross Lecture Hall, Bronx River Parkway at Fordham Road, the Bronx, 800-322-6924, $10.

PAINTINGS

HAVING THEIR SAY The title of a group show at Monya Rowe Gallery, “Get Up Off Our Knees,” is a response to what the artists perceive as the public’s underlying fear of artistic expression. Angela Dufresne, Vera Iliatova, Amy Longenecker-Brown, and Caroline Walker exhibit works that celebrate emotions and how people communicate them. Ms. Dufresne’s “Girl Looking Over the Divide (From ‘The River’)” (2008), above, is among the works on display. Through Saturday, June 7, Tuesday–Saturday, 11 a.m.–6 p.m., Monya Rowe Gallery, 526 W. 26th St., room 605, between Tenth and Eleventh avenues, 212-255-5065, free.

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