1. The fourth edition of Building Fashion's cutting-edge design series will be a pop-up Richard Chai store open from October 21 to 31, noon - 6 p.m., under the High Line at HL23 (504 West 24th Street). The retail installation was designed by Snarkitecture.

2. More action tonight (October 19, 8 p.m. to 10 p.m.) at the Levi's Photo Workshop (18 Wooster Street) () with the opening of "1001 Images" by Nick Zinner, guitarist of the Yeah Yeah Yeahs.

3. The Invisible Dog Art Center (51 Bergen Street, Brooklyn) opens tonight, October 19, 6 p.m. with an installation by Ian Trask and a performance piece called "Batterie" by David Wampach and Anders Griffen.

4. Another new gallery, Indica On 11th, (150 11th Avenue) is opening on November 18, 6 to 10 p.m. with a group show called "Dirty Little Secrets" with works by Tobias Keene, Laura Keeble, Paul Hazelton, K-Guy and Nicholas Bowers. The show was curated by Wendy Worth Asher.

5. Stop by hot tub hotspot  Le Bain on Wednesday, October 20, for "Nouveau York" with DJs Dr. Dunks, Eli Escobar, Jacques Renault, Justin Miller, Stretch Armstrong and more.

6. Get used to hearing about John Baldessari. A major retrospective, "Pure Beauty," opens tomorrow at the Metropolitan Museum of Art (1000 Fifth Avenue) and there's an exhibition of new Baldessari works opening on October 21 at Marian Goodman Gallery (24 West 57th Street). Also, Gemini G.E.L. at Joni Moisant Weyl (980 Madison Avenue) has an exhibit of six prints up until November 6. Hudson Hills Press has new catalogue raisonne' of his prints and multiples.