Rodan + Fields was recommended to me by a former boss with impeccable skin, so I decided to try out the Unblemish line. This toner is designed for "spot fading," which means that it contains elements that lighten the redness from scars, age spots, random discolorations, etc. You don't put it all over your face; it's just used on spots that you'd like to match the rest of your skin.
When you're looking for a gentle toner that will safely get rid of skin blemishes, you want one that has hydroquinone in it as the active ingredient. That's what makes skin lighter and has proven to do so. This Rodan + Fields product has 2% hydroquinone. Compare that with some others that you can buy in the pharmacy and you may see much less hydroquinone in it.
They suggest using this toner for several weeks, so don't expect an immediate, overnight change. But it does work, and it doesn't leave your skin cracked and dry. The creators, Rodan + Field, are dermatologists, so you can trust that it is safe. I've even been using a cotton swab and putting a little but of toner under my eyes to help lighten up my dark circles. I also used it on the side of my face where I had some acne scarring.
The only down side is the price. Given that the dermatologists who create it use extensive research and the best ingredients, it's not sold everywhere and may be more expensive than some are willing to pay. But if beautiful skin is your thing, you may want to consider trying this out.