One & Done Serum

One & Done is a multi-active face serum designed to address multiple everyday skin concerns in one step—including dark spots, uneven skin tone, dehydration, dullness, uneven texture and early signs of ageing. It combines brightening, hydrating and peptide-based actives in one formula.

One & Done is formulated to target dark spots, post-acne marks, uneven skin tone, dullness, dehydration, uneven texture, redness, under-eye puffiness and early signs of ageing.

Yes. The formula contains Niacinamide, Tranexamic Acid and Ethyl Ascorbic Acid, alongside antioxidant ingredients, to help improve the appearance of dark spots and uneven pigmentation with consistent use.

One & Done is formulated to help improve the appearance of post-acne marks and uneven skin tone. Its brightening system combines Niacinamide, Tranexamic Acid and a stable Vitamin C derivative.

Yes. Alongside its corrective actives, One & Done contains Sodium Hyaluronate, Olive Squalane, Saccharide Isomerate, Aloe Vera and Betaine to support hydrated, comfortable and smoother-looking skin.

The formula is designed to support a healthy, resilient skin barrier through hydration, conditioning ingredients, fermented ingredients and peptides. It is best positioned as a multi-corrective serum that supports barrier health rather than as a dedicated medical treatment for a damaged skin barrier.

Yes. One & Done contains a multi-peptide complex, including Acetyl Hexapeptide-8, Copper Tripeptide-1, Palmitoyl Pentapeptide-4, Palmitoyl Tripeptide-1, Hexapeptide-9 and Tripeptide-1. These ingredients are included to support firmer, smoother and healthier-looking skin.

The peptide-rich formula is designed to support smoother, firmer and more youthful-looking skin while addressing hydration and uneven texture. It combines several peptides with antioxidants and skin-conditioning ingredients.

Yes. Its combination of Niacinamide, Tranexamic Acid, Ethyl Ascorbic Acid and antioxidant-rich botanical extracts is designed to help improve the appearance of uneven tone and dullness.

Yes. Terrai recommends applying 2–3 drops to the face and neck morning and evening after cleansing, followed by moisturiser. SPF should be used as the final step of your morning routine.

Yes. It can be used AM and PM. When using it in the morning, always follow with sunscreen to protect your skin from UV exposure and support your pigmentation-care routine.

Yes, but because One & Done already contains multiple active ingredients, you don't necessarily need to layer several additional treatment serums. A simple routine of cleanser → One & Done → moisturiser → SPF in the morning is sufficient for most people.

One & Done has undergone in-vivo hypoallergenic and skin-irritation testing. However, individual skin sensitivity varies, so patch testing is recommended if your skin is particularly reactive or you're introducing multiple active ingredients for the first time.

The serum is designed to address concerns including post-acne marks, uneven tone and dehydration. If your skin is acne-prone or highly reactive, introduce it gradually and patch test first.

Apply 2–3 drops to your face and neck after cleansing. Allow the serum to absorb before applying moisturiser.

Visible results vary depending on your skin, concern and consistency of use. Pigmentation and post-acne marks generally require consistent skincare over time rather than overnight correction. The product has undergone in-vivo clinical testing, so the specific study results should be displayed alongside the FAQ rather than promising a fixed timeframe that the study does not establish.

It contains Ethyl Ascorbic Acid, a stable Vitamin C derivative, but it is not a single-active Vitamin C serum. It combines Vitamin C with Niacinamide, Tranexamic Acid, peptides, hydrating ingredients and antioxidants for a multi-corrective approach.

Yes. Tranexamic Acid is included as part of the serum's brightening system alongside Niacinamide and Ethyl Ascorbic Acid, targeting the appearance of dark spots and uneven skin tone

Yes. It contains Sodium Hyaluronate, a form of Hyaluronic Acid used to support skin hydration and a plumper, smoother-looking complexion.

Yes. Terrai lists an in-vivo clinical test report, in-vivo hypoallergenic test and in-vivo skin-irritation study for One & Done.