Limited Edition designer, Marni, will launch in mass retailer H&M tomorrow (Thursday) opening at 8am.

The catch, you're not going to have time to casually come in on your lunch break. Probably what you are looking for will be gone. Expect people lining up in the middle of the night to purchase that coveted item they've been fantasizing to wear.

H&M anticipates the high aggression. They are handing out 300 bracelets in 10 different colors. Each color has 15 minutes to shop, with 5 minutes between slots. For the common shoppers, don't sweat it, the bracelet system only apply for those shopping for Marni.

All the retail stores will open at 8am tomorrow. For the complete list of stores click here. To check out the look book and prices head on over to Fashionista.

Refinery 29 spoke with H&M spokesperson Jenifer Ward to offer insight on this upcoming event concerning the types of people who will be shopping: "They're very calculated, and they're looking to get their hands on the specific pieces they want. So they come in knowing exactly what they want, and they're asking for it, and they're running to get it." She expects shoes and necklaces to go first and encourages people living in New York and L.A. to get there in "the middle of the night."

Ward also suggests to come back a few days later, after customers return the items, to try and find anything you couldn't get on your first attempt. Ward explained later on about some customers tweeting when they released a Lanvin collection last year: When we did Lanvin last November, we had somebody going on Twitter saying there was a stabbing outside of H&M - which was absolutely not true! They obviously did it so people would get scared and not line up, and there was no such issue, not even close (though we did have the police come in and investigate, just to make sure)."

The advise: match the standard Ward describes the shoppers targeting specific pieces- know exactly what you want. Not sure yet? Check out a few pieces from the collection below to get the heart pumping.