Chicago brother/sister duo White Mystery — Miss Alex White on guitar and vocals and Francis Scott Key White on drums — have only one stated purpose: to dedicate themselves, fully and completely, to rock and roll. They won’t get haircuts. They won’t date. Their tour schedule for the remainder of June, in support of their most recent album, “Dubble Dragon,” includes 13 states (they’ll be at Cafe Nine in New Haven on Tuesday, June 17) and a gig in Toronto. It’s better that way. Let them concentrate on playing.

We asked the Whites via e-mail about playing together as siblings, how they kill free time on the road and the significance of 4/20.

CTNow: You guys have been incredibly prolific over the last few years — four full-length albums and an EP, and probably a lot more I’m not even aware of. What gets you inspired to write new stuff?

Francis Scott Key White: White Mystery is inspired by feelings of love, excruciating pain, exhaustion, and other secrets I’m not allowed to talk about.

CTNow: White Mystery was allegedly formed on April 20, 2008. “Dubble Dragon” came out on 4/20 of this year, and you spent the last 4/20 performing in the Netherlands. Any chance we’ll get a stateside 4/20 White Mystery performance in the next couple of years?

FSKW: Alex White actually has a cyborg heart that was engineered by a clockmaker in the Netherlands. We must return once a year to wind her back up and calibrate her missile systems and eyebeams, so we decided to play shows to pay for our plane tickets.

Miss Alex White: White Mystery hosts a 4/20 show every year in a different city; this year was the first in Amsterdam.

CTNow: The new record “Dubble Dragon” is a double album, with one half devoted to new studio tracks and the second a live show. What can you tell us about the decision to do that this time around?

Both: We wanted to release a live album, and we also wanted to put out a double album, so we decided to kill two dragons with one magic stone.

CTNow: Being brother and sister (I’m sure you’ve been asked this a lot): is there a special kind of (unspoken) communication that makes it really easy to play together? Do you fight like brothers and sisters often do?

Both: The fighting is often unspoken and takes place in a neuro-telepathic-realm.

CTNow: Do you remember the first time you ever played together? What did you play?

Both: The first time we played was at ages 4 and 6 years old in the “Baby Blues” when we originally wrote the song, “Buttheads from Mars.”

CTNow: When you roll into a new town (assuming there’s time), what do you like to do?

FSKW: Have a shot, beer, and a toke then put “Master of Puppets” on the jukebox.

MAW: Eat a green apple, drink coffee, do jumping jacks, take a nap.

CTNow: Do you remember the first record you bought with your own money? The most recent?

FSKW: I starved myself in the 8th grade to spend my lunch money on ICP’s (Insane Clown Posse) “Riddlebox.” And I spent 25 euro on [Metallica’s] “And Justice For All” at the last Virgin Mega Store while on tour in France.

MAW: I bought 20 vinyl singles (45s/7″) at Used Kids Records in Columbus, Ohio. White Mystery played an in-store performance there with Dirty Fences, and the shop gave us store credit as payment, so I stocked up on Gary Glitter gems, the Monkees, Box Tops, and more.

CTNow: Any current musical obsessions? Literary ones?

MAW: Sam Flax “Fire Doesn’t Burn Itself.”

WHITE MYSTERY performs on Tuesday, June 17, at Cafe Nine in New Haven, with Mr. Elevator and the Brain Hotel and Medication opening. Showtime is 8:30 p.m. Tickets are $8 to $10. Information: cafenine.com.