Which Beauty Products and Treatments Really Work?

Getting it Straight: Bumble and Bumble Concen-Straight Smoothing Treatment

An at-home de-frizzing system.

After tranquilizing my toddler one recent evening with seven readings of Good Night, Gorilla, I retired to my bathroom with Bumble and Bumble's Concen-straight Smoothing Treatment ($45; bumbleandbumble.com), which claims to "smooth hair for manageability and frizz reduction for up to 30 shampoos." Here's how the night progressed:

7:30 Wash my hair. As directed, don't condition.

7:40 Comb through my very tangled, unconditioned hair.

7:46 Saturate my wet hair with the straightening solution, from roots to ends. The smell—kind of sulfuric—isn't pleasant, but it's not totally noxious.

7:58 Start a 30-minute timer. I'm not supposed to touch my hair, pull it back, or tuck it behind my ears. (The straightener contains sodium metabisulfite, a chemical that breaks the bonds in the hair so it can be re-formed in a new shape—straight, if you keep it flat, or with weird kinks, if you pull it back.)

7:59 Try to ignore the nearly irresistible urge to tuck my hair behind my ears.

8:05 Inform my husband he'll have to do the dishes because I can't tuck my hair behind my ears.

8:20 Realize I was supposed to be combing my hair (to keep it straight) every five minutes. Comb my hair.

8:28 Get back in the shower to rinse out the solution.

8:45 Blow-dry my hair.

9:05 Start flatironing my hair, as directed, in one-inch sections.

9:25 Still flatironing. My hair is fine-ish, so the directions say I should go over each section two to three times (as opposed to seven to ten times for thicker, coarser hair).

9:45 Finally finished. Now I must wait at least 24 hours before shampooing and must not "pin, crimp, bind, or put behind ears until after first shampoo."

Four weeks later: After that first shampoo, my hair was easier to style. It dried more quickly and smoothly. On rainy days, I didn't have a halo of frizz. After the fifth wash, though, the results were wearing off. And after the tenth—about three weeks in—my hair was back to its old self. Would I do it again? In the hair-poofing dog days of summer—probably. The rest of the year? I'm not that patient. —Jenny Bailly