“Stranger Things” actor David Harbour brought pop star girlfriend Lily Allen to a Skin Cancer Foundation event at the Plaza.

The two have been linked since August — and were photographed kissing in New York last week — but they’d never walked a red carpet together.

Also at the starry Champions for Change Gala that raised $700,000 were Katie Holmes, Sebastian Stan, Dianne Wiest, and ICM Partners bigwig Adam Schweitzer and wife Stephanie, who co-chaired.

Fresh off hosting “SNL,” Harbour’s a star in Scarlett Johansson’s next Marvel movie, “Black Widow.”