Editor's TipEditor's Tip

Before applying this leave-in serum, wash your hair with Kérastase’s shine-boosting Cristalliste shampoo and conditioner.

Kérastase

  • 4.1 out of 5 stars, based on 760 Reviews 760 Reviews Write a Review
  • $42.00 includes Free Shipping
  • 50ml   
  • Availability: In stock

    $42.00

Birchbox Breakdown

Ever since we watched the first season of “Gossip Girl,” we’ve been huge fans of Blake Lively’s flowing waves. So we were excited to learn that the blonde actress was the inspiration behind Kérastase’s new serum. Specially designed for long hair, the leave-in treatment adds a high-definition shine while sealing each cuticle (bye bye, split ends). Plus, the light, gorgeously scented formula won’t weigh down your strands.

How to Use

This luxe serum is made with sophisticated light reflectors to add mega-gloss and shine while smoothing away frizz. A generous amount of aloe vera—high in natural amino acids and vitamins—softens and restores dry, brittle ends (the number one problem for girls with long locks).

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Product Reviews & Sample Feedback

760 Reviews
4.1 out of 5 stars
5 Star
314
4 Star
277
3 Star
129
2 Star
29
1 Star
11
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Most Helpful Customer Reviews

Just Ok...
Purchased

i bought it based on the rave reviews and the super shine this gives. First, I have grown to LOVE LOVE Kerastase (Architect) line and when I use Fibre Architet, the shine it gave with a small pump is amazing. I bought this because there is more in the bottle (1.7 oz) but the shine factor is not as good. The smell is a strong alcohol smell with a hint of flowers and I don't see that it does anything special to my hair (in terms of health). I would stick to the green line next time or use Gold Lust oil which to me is the best at shine factor (and amount of product). Not their best from K.

3
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Works wonderfully!
Purchased

I bought this without trying a sample based on some research I did, looking for a product that would help make my long hair more silky smooth and shiny. I blow dry my hair a lot and so it can be really dry. This product works great to give me nice shine and smoothness. I have fine hair and this product doesn't weigh it down - and smells so good. I love the scent - it's a light, clean smell that reminds me of a floral shampoo. The size (1.7oz.) is also really good for me for traveling. I take it on all of my trips. Yes, it's a small bottle, but even with long hair you don't need a lot of it. One pump, rub in your hands and put through your ends. It's working better than anything else I've tried. It's now become one of my favorite hair products. I'll certainly be ordering more!

5
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Leaves hair so soft
Purchased

I can't live without this serum. I have long, slightly wavy hair, with a ton of fly aways. I always thought my hair was soft prior to using this product but after being introduced to this stuff, my hair world has completely changed! It keeps all of my baby fly aways down making it look super sleek, smooth, and shiny (the shine that you see in commercials). My hair has never been so soft! 1-2 pumps won't leave your hair feeling greasy or weighed down but will leave you with gorgeous bouncy hair.

5
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Smells great
Purchased

I love anything that makes the hair silky and it smells great and this did both of those I apply while hair is still wet and I love the smell of this

5
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Nice Product
Sampled

This product works great. My hair was shiny but not oily or greasy. I also really liked the smell. I've tried other products but my hair is always greasy or oily after. I will definitely be buying this!

4
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LOVE.
SampledPurchased

I use this every day. It's incredible! My hair feels amazing whenever I use it and it is the only product I've ever used that helps moisturize my dry ends. I wish I could bathe in this product.

5
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Hair serum
SampledPurchased

I love this product! I received it in my birchbox and just had to purchase the full size. It smells amazing and adds a lovely shine and smoothness to my ends. It's the perfect product for long fine hair - it detangles, adds shine and softness to my dry ends, is a heat protectant on my long hair and its the best smelling product!

5
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Hand to return
Purchased

This was to heavy for my fine hair. I ended up returning it. It was to bad because I really liked the smell!

2
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Wonders on split ends
Sampled

This product really does work. I used it on my hair and although I don't have bad split ends, it still did a good job at the little amount I had

4
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Amazing
Purchased

This stuff lives up to the hype. Smooths my split ends and makes my hair so shiny. Glad I finally bought it!

5
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