The Placebo was founded in 1999 by a bunch of teenagers who wanted all-ages and drug- and alcohol-free shows. Since then, it’s had a hard, rocky road, getting kicked out of many venues.

Now it is gearing up for it fourth annual Punk Rock Prom. This year’s theme: Invasion of the Prombots.

With the musical stylings of:

• The Social Ills – Eureka punk

• The Psycho Nubs – Richmond, Ind., garage punk

• The Fortyhands – Arcata punk/ska

• La Plebe – San Fransisco punk

• The Monster Women – sci fi espionage indie rock

• Blancatron – robot rock

Placebo member, event organizer and all-ages concert activist Jasmine Loucks saidm “There are high school proms, (which are) a very cliquey event with a popularity contest thrown in. Punk Rock Prom is an alternative to that.”

Dao (no last name), also an active Placebo member and event organizer, said, “We are kind of making fun of it, (but) at the same time providing a space for people to do prom as much as you want.”

Dressing up is encouraged, whether as a “Prombot” or in a full tuxedo or ball gown. Either way, those dressed up will get in for a cheaper price. The event is $5 with a costume and $7 without. Placebo membership is required and can be purchased at the door for $2.

Loucks said she is hoping to see a good mixture of old-school robotic cardboard box costumes and full prom getup.

Previous Punk Rock Prom themes have been Zombie Prom, Devils and Angels, and straight-up Punk Rock Prom.

In addition to the head-banging lineup, there will be information tables for nonprofit groups.

The Punk Rock Prom is taking place at the Bayside Grange on April 25 and will start at 7 p.m.