Kate McKinnon on Being an Electric Toothbrush Fairy for Philips Sonicare, Her New Children’s Book and Working on ‘A Minecraft Movie’

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Kate McKinnon is known for playing a cast of many characters — and now she’s adding a tooth(brush) fairy to that list.

Best known for portraying a Ghostbuster, Hillary Clinton, cat lady Carole Baskin, Olya Povlatsky and Justin Bieber (to name but a few), the Emmy-winning comedian stars in a new campaign for Philips Sonicare as Susan Toothbrush, a mythical mascot of oral healthcare. In the 15- and 30-second ad campaigns, the former Saturday Night Live star magically pops up in people’s bathrooms to help them swap their “ancient bristle stick” with the company’s electric toothbrushes.

“She’s immortal and that’s part of her mythology,” McKinnon tells The Hollywood Reporter of her and Philips Sonicare’s latest comedic creation. “When I’m doing anything, I always need to know what the characters are wearing and what’s the hair doing and what do they look like. … At SNL, I was always so lost until I had the wig. And even Susan Toothbrush — I must shout out my longtime collaborators, [makeup artist] Cassandra Garcia, [hairstylist] Joseph Maine and [stylist] Rebecca Grice, who we built the look together. We talked at length about what’s the hair, she’s mythical but she’s cool, what does that look like? We just built this look with the brand and I love that.”

McKinnon also recently stepped into another role: a New York Times-bestselling children’s author. The 40-year-old Barbie star released her first book, The Millicent Quibb School of Etiquette for Young Ladies of Mad Science (Little, Brown Books for Young Readers), on Oct. 1.

Written for ages 8 and up, the 256-page tells the story of adopted sisters Gertrude, Eugenia and Dee-Dee Porch, who stick out like sore thumbs in the town of Antiquarium and at school. After getting booted from Mrs. Wintermacher’s Etiquette School, the quirky trio receives a mysterious invitation to attend a new academy run by the infamous mad scientist, Millicent Quibb. (Readers don’t have to imagine McKinnon’s voice as they turn the page — the author also narrates the audiobook version.)

“This image of these three weird little mad scientists came to me in my mid-20s and I couldn’t let it go. And I loved them so much and I just wanted to write a story about them. And then 12 years later, here we are,” McKinnon says.

The actress next will appear in A Minecraft Movie, which also stars Emma Myers, Sebastian Eugen Hansen, Jason Momoa, Jack Black (as the original video game character, Steve), Jemaine Clement, Danielle Brooks and Jennifer Coolidge.

McKinnon recently sat down with THR over Zoom to share why she “loves going to the dentist,” how she knew that quirkiness was her superpower (she detailed this when she made her SNL hosting debut last winter), the origin story of her book, what she knows about the highly-anticipated video game film and more.

A lot of things probably come across your desk, and you’ve only done a handful of commercials and partnerships. What made you say yes to Sonicare?

Well, I do really believe in the product. It is the toothbrush that helps me feel like I’ve been to the dentist every time I use it, so I was very flattered to be approached by them. And I also just really liked the idea that they came to me with, which was popping up in people’s bathrooms and helping them make better decisions about their oral healthcare, i.e. making the “Sonicare Switch.” They were so collaborative and we came up with this character Susan Toothbrush, who materialized through walls. That’s her power and she knows what’s up in the toothbrush department. She is able to get people to ditch their manual toothbrushes in favor of a Sonicare.

I enjoyed the one about the guy headed to a job interview.

It is actually true. Two minutes of brushing with a Sonicare is the equivalent of a month of brushing with a manual. And I learned that and I was like, “Oh my, what was I doing all those years?”

Philips Sonicare DiamondClean Smart 9300 Electric Toothbrush

Not to put your oral health on blast, but what’s your routine — are you a once, twice-a-day brusher? There are some people I know who brush after every meal.

Wow. I mean if you’ve got the time, go for it. But I really like how it makes my teeth just smooth as glass and that’s such a good feeling. I love going to the dentist, but you can only go every six months. And so I love being able to have that fresh, clean, pristine feeling twice a day.

So when you go to the dentist, you get the A-plus.

I do need to have done everything right, so yes, I love getting good feedback from the dentist.

When you were working with Philips, were there any ideas that got left on the cutting room floor? I’m sure you came up with a lot of wild characters.

No, it was sort of like Susan Toothbrush just came into being and it was immediately like, “Oh yeah, Susan Toothbrush.” Susan Toothbrush is immortal and that’s part of her mythology as well. But then it was more about what is the look of Susan Toothbrush and is she in a toothbrush mascot suit? And then it was just sort of like, no, it needs to be sophisticated and cool. And so we landed on that look and I’m just really happy with how it all came together.

Your new children’s book is currently part of my family’s bedtime routine. It really speaks to me as an adult who is also a fellow Roald Dahl fan and it feels like there is so much of you in the characters. How autobiographical would you say it is?

It’s not autobiographical obviously because it’s fantasy, but it is absolutely my story and metaphor. I definitely feel at once like I’ve reached a point in my life where I’m more like Millicent Quibb, the mad science mentor who’s a little misunderstood but just wants so badly to help and reach out to a younger generation. And also when I was growing up, I felt so much like the Porch sisters, the protagonists who just are out of step with their environment and are just yearning for a mentor who can understand what’s special about them in this town where people think they’re just not worth very much.

I heard your interview on NPR where you mentioned that Millicent Quibb was over 10 years in the making. What was the first nugget of the story?

Honestly, it was a drawing of these three little girls with wacky hairdos who I knew were mad scientists. When I’m doing anything, I always need to know what the characters are wearing and what’s the hair doing and what do they look like. And I was surprised by that. But whether it’s the book where I had to know what they looked like, or at SNL, I was always so lost until I had the wig. And even Susan Toothbrush — I must shout out my longtime collaborators, [makeup artist] Cassandra Garcia, [hairstylist]Joseph Maine and [stylist] Rebecca Grice, who we built the look together. We talked at length about what’s the hair, she’s mythical but she’s cool, what does that look like? We just built this look with the brand and I love that.

And so anyway, the point is the art, this image of these three weird little mad scientists came to me in my mid-20s and I couldn’t let it go. And I loved them so much and I just wanted to write a story about them. And then 12 years later, here we are.

You mentioned earlier that Susan Toothbrush’s superpower is materializing through walls. In the book’s intro, you wrote how your mother encouraged you to march to the beat of your own drum. How did you know that your quirkiness was your superpower?

I mean, yes, there’s exactly the message I wanted to convey and because there have been, I think it’s a lifelong journey-slash-struggle-slash-adventure to come to a fork in the road and you can choose to have the courage to do what your actual heart and authentic self are telling you to do. Or you can do what is expected of you, which is usually two different things. And there are times when I’ve chosen to do the authentic thing and there are times when I didn’t have the balls and I did the inauthentic thing, and those were the times that I fell in my face. And the times that I really put something out there that connected with people were the scariest things because I was taking a risk.

I just think that the world doesn’t need you to copy someone else or try to be something you’re not. The world in order to grow needs every person to be exactly what they are. And I think it’s just important to keep telling kids that.

We’re at the part in the book where Gertrude Porch has to demonstrate how to sit on a fainting couch in front of her class and makes a contraption with her pet bat. It reminds me of that sense of creativity I used to have as a kid that I feel like I’ve sometimes lost as an adult. As cheesy as it sounds, how do you manage to hold onto that sense of wonder and magic?

Well, you mentioned Gertrude and how she has to sit up straight. So she brings this invention that she made, which is like a bat tied to a vest and the bat pulls her spine up. I had so many moments like that when I was growing up where I would bring some fakakta thing to school, like I made a motor once… I just thought people were going to be excited and it just fell flat. I drew a rose and I put it in this boy’s locker. He was so gracious, but it did not net me a relationship.

It’s scary to follow through on your big ideas, but I again find that that’s where the best stuff comes from. If you have this kernel of genuine passion for it, for an idea that you have, and it seems kind of out there, I just think that’s what people end up connecting to the most. And I found that to be true in all different forums that I’ve worked in. I mean, so long as it’s legal!

So now that the book has been out for a few weeks, what are you hearing from young readers that is bringing a smile to your face?

I got to go around to some schools and some independent booksellers across the nation and meet the young readers for whom the book was intended. And oh my god, it made me so happy because they were so curious and so enthusiastic about science and about nature and I think that it’s really encouraging to see young people being interested in the earth and loving the earth. It just was. And they’re so funny and they’re so cool, and I loved meeting them. It’s true that everyone does have their own magic and it’s so important as adults to foster that in the children around us.

Pivoting to another kid-related topic, you’re in A Minecraft Movie. I’ve already seen kids at the movie theater who can quote the trailer from start to finish. What can you tell us about your character and working on the film?

I can’t say about any of that, except I will say I’ve seen the animation and I think it is so special and it looks so incredible. And on the theme of creativity and not losing your creativity, I think it’s going to be an anthem for that. And I’m very excited to see the film.

Had you played the video game before?

I do not have technology in my life, so TBH, no. [Laughs] I’m as analog as possible. But I think as far as games go, games that involve imagination and building. I think that’s great.