@ Harvey Milk Civil Rights Academy, 4235 19th Street. Join the fun at this annual costume parade around the Castro followed by a dance party in the schoolyard. All families are welcome and costumes are optional. 2:30 pm–3:35 pm. Volunteer info: https://www.signupgenius.com/go/30e094ca8ab22a5fe3-hmcra1

@ Castro Farmers’ Market, Noe Street Between Market and Beaver. The Castro’s own weekly farmers’ market invites you to join the fun of decorating pumpkins and also to check out the season’s fabulous selection of fruits, vegetables and much more. 4–8 pm. http://pcfma.org

@ SFFD Station 7, 2300 Folsom Street. This family-friendly neighborhood event, hosted by the Central Mission Neighborhood Organization, begins at the Fire Station where you can check out the fire trucks, enjoy the costume contest and win prizes from local businesses. 5:30 pm. https://www.facebook.com/events/351670338708221/

@ Standard Deviant Brewing, 280 14th Street. Launch your evening by sharing a drink, socializing and writing letters to get the vote out for the 2018 midterm elections. 6–8 pm. http://www.standarddeviantbrewing.com

@ Dog Eared Books Castro, 489 Castro Street. Scaaary stories are welcome for this special open mic hosted by Tony Vaguely, Kathy Queer and Connie Champagne. 7 pm. http://www.dogearedbooks.com

@ The Independent, 628 Divisadero Street. Smoked out soul. 8 pm https://ticketf.ly/2yGy8bq

@ Oasis, 298 11th Street. Dust off your wooden stake, get your garlic and holy water ... it’s vampire season! Show starts at 8 pm. https://sfoasis.com/events/buffy-the-vampire-slayer-live2018

@ Friends of the San Francisco Public Library, 710 Van Ness. With a Halloween theme this year, the largest book sale on the West Coast encourages costumes based on your favorite character, and the chance to peruse more than 500,000 books priced at $2–$4. 8 pm. http://www.friendssfpl.org

@ The Fillmore, 1805 Geary Street. The iconic rockers present a Halloween show. 8 pm. http://www.thefillmore.com

@ Gateway Theatre, 215 Jackson Street. Directed by John Fisher with music director Sheela Ramesh, the show takes you down under with the late great performer Peter Allen (1944–1992), whose original songs are featured. Through November 17. http://www.therhino.org

@ Elbo Room, 647 Valencia Street. The Misfits tribute band Astrozombies brings their annual Halloween show to The Elbo Room as the venue’s final October 31 celebration. http://www.astrozombiessf.wordpress.com

@ San Francisco Old Mint, 88 5th Street. The underground vaults of the Old Mint are the setting for a terrifying new attraction hosted by Into the Dark and co-created by Peaches Christ. Multiple tour times through November 3. http://www.intothedarksf.com

@ The Stud, 399 9th Street. Dance the night away with international music masters Violet from Lisbon, Portugal, and Photonz of London. 9 pm–4 am.