I Tried Crown Affair's New Overnight Hair Repair Serum to Heal Breakage and Minimize Frizz

If there's one thing to know about my beauty philosophy it’s that I need my products to work hard so I don't have to. I want a skin tint that doubles as a hydrating serum as it disguises and treats my dark spots. I need a luxe body wash that can fight keratosis pilaris bumps while also leaving my skin soft and smelling absolutely delicious. And for as relatively low-maintenance as I am with my type 2b wavy hair (meaning I rarely use hot tools to style it for daily wear) I still need products that can heal breakage, smooth frizz, and repair the damage that comes along with coloring it blonde and wearing a slick back bun on the regular.

So, when one of my all-time favorite hair care brands revealed that a new repairing serum was coming soon (the perks of being a beauty editor: you get the inside scoop on new product launches before they hit the store shelves) my interest was piqued. Soon I was unboxing the new Crown Affair Overnight Hair Repair Serum with hopes that it could transform my very long hair—which is currently suffering from the aftermath of a summer spent by the pool and at the beach—into a smoothed, silky, and appropriately hydrated mane.

Here's what happened when I tested the serum for three weeks.

The Formula

To start, there's a treasure trove of good-for-your-hair ingredients in this serum, which the brand is calling a "Superfood Blend." True to the Crown Affair DNA, Tsubaki oil makes an appearance, along with meadowfoam seed oils, flaxseed, and chia seed extracts to repair and strengthen. Rosemary leaf, arguably one of the beauty industry's most buzzy ingredients right now (especially when it comes to treating hair loss) is also included, although for this formula its main purpose is to boost shine, softness, and compatibility overnight—I'm not quite sure what the last benefit means but I guess I'll take it as opposed to having incompatible hair.

The lightweight, creamy serum also leaves your hair smelling divine and quite expensive. Crown Affair is known for its Signature Scent Hair Perfume so I'm not surprised that this newest launch also includes the bergamot, green tea, and sandalwood blend.

This is also the first product from the brand that has third-party clinical testing, which is a big deal for any brand but especially those not owned by a huge conglomerate since the process is extremely pricey. The results after a four-week clinical study showed that the serum was able to strengthen hair 2x after one use, smooth and soften 2x after one use, reduce breakage by 75 percent in one month, and provide eight hours of frizz protection. Needless to say, I was eager to give it a try.

The Application

For context, I usually wash my hair in the morning every three to four days. Day two and three hair typically still looks good enough to wear down, especially since I love a messy, lived-in look but after that, I usually throw it up into a bun or a braided ponytail. That tension isn't great for my hair, so I tend to use a moisture mask once a week on my Big Wash Day, but I don't always take the extra time. So the idea of applying this serum nightly before falling asleep is the perfect compromise in theory.

However, the brand does advise that you brush it through your hair after you apply it to the mid-length and ends. That doesn't work for my hair type, at least not if I want to wear my natural texture the next day and not reach for a flat iron or three-barrel waver. Instead, I use four to five pumps of the serum, warming it up between my palms, and apply it using the "prayer hands" technique like I do with my air dry gel and leave-in conditioner after the shower.

I appreciated that as soon as the product dried down a little bit (which only took a few seconds) there was no tacky or sticky residue left over. That's the worst feeling to have on your hair when you're laying down for the night. My ends, which are in desperate need of a trim, also didn't feel as tangly or chaotic. That one-use claim definitely lived up to the hype. I also didn't wake up with any funky shapes or flattened sections, which is always a risk when you have textured hair. Truthfully, it didn't really feel like I had done anything to my hair except run my fingers through the ends to distribute the product a little bit.

The Results

Despite the instant softness I felt after the first application, no product that claims to repair your hair is going to do so after just one use. Beauty formulas, whether skincare, body care, or hair take time to yield results, and this Crown Affair serum is no different. But I am the prime candidate to use a product like this considering my hair is textured (so it's dry and more delicate than straight hair) regularly highlighted (so it has bleach damage) and I subject it to high-tension styles (I'll never relinquish my slick back bun, thank you very much) on a weekly basis.

The next biggest difference I saw in my hair was in the shower when I was trying to detangle. I usually use a wide-tooth comb to evenly distribute my conditioner before rinsing, but I tend to encounter a lot of tangles, especially after a day at the beach or a sweaty workout. I did both things during the course of testing this formula and I was pleased to see that I could more easily work my comb through my wet hair—a sign that the damage isn't as severe. Damaged hair has a raised cuticle (the outer layer of the hair) which can lead to more tangles, dryness, and breakage. Clearly, the benefit of applying the serum almost every night—I'm human, not perfect—showed up in the smoothness and overall condition of my hair.

As for my split ends, I really just need a trim to get rid of them, but I don't think my hair looked as wild and ratty on the ends as it can tend to do when I've gone this long without a cut. But the frizz I think stayed relatively the same considering I don't love a blowout, the best and fastest method to smooth flyaways. I'd be eager to see how this serum works for someone who does regularly heat style as I predict it would deliver a very nice, silky finish.

The Takeaway

Like I said, I'm all about a product that works while you're sleeping. It's why I'm such a massive fan of using night creams and retinoids to wake up with smoother, glowing, more radiant skin. And considering I'm not planning to give up my four-times-a-year blonde color sessions or my snatched bun routine it's probably wise to level up my hair repair game with this Crown Affair serum. I still have another week to go before I reach the recommended one-month time frame to see the full results, but if this formula stacks up as well as my other favorite products from the brand, I'm expecting to have some exceptionally good hair days this fall.

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