Someone Get This Girl Some Conditioner!
Most likely that's a dirty weave Mischa Barton is wearing. Seriously that thing looks fried. If it's a wig, weave, real hair, whatever...that thing needs some moisture. All she has to do is pop some baby oil on that shit, damn!
You know the horse that owns that mop is pissed off that she's not taking good care of his mane!