The actresses have been named the new celebrity ambassadors for the Procter & Gamble owned brand, fronting TV, print and in-store advertising set to launch this July.
While Mendes has steamed up countless Calvin Klein Jeans ads and Watts has gone glam for Ann Taylor's fall campaign, the famous faces are now lending their locks to Pantene.
Donning sexy, brunette curls, Mendes will support the Breakage to Strength collection, a line designed to repair damaged hair, an issue that hits home for the 37-year-old star.
"The amount of torture I put my hair through with flat irons, blow dryers and curling irons leaves my hair extremely damaged," said Mendes. "With Pantene I can use all of these tools and still keep my hair healthy," she continued. "It's amazing to be working with a brand like Pantene that is so honest; there were no tricks on the set of the photo shoot. Each look was natural and never manipulated and my hair looked healthy and beautiful for every shot. Pantene products truly live up to what they promise."
Watts's shiny golden strands will support the Flat to Volume Collection -- and she's keeping it real by sporting her natural hair in the ads, skipping extensions, texture-altering chemicals or other hair tricks to prove the line really gives her a much-needed boost.
"I am excited to join the Pantene family. I want to let women with fine hair know that achieving beautiful, voluminous hair is possible without damaging your hair or adding extensions," said Watts. "I am truly blown away by the research and science that goes into making Pantene. No matter what your hair type is, you can find a Pantene product that will give you the result you are looking for."
Watts adds, "Since I became a mother, the time I have for myself has shrunk dramatically. Also, I have never been able to do my own hair. So I am thrilled with Pantene because the quality of the products helps me get the volume I want with very little effort at all."
Chosen for their "unparalleled honesty and willingness to share their truth as women," we can't wait to see Mendes and Watts blossom into their new roles as hair ambassadors for one of our favorite drugstore brands.
Click here to read what happened when I washed my own hair after five years with Pantene's Pro-V Curly Hair Series.