Be afraid! Be very afraid! Bonnie McKee offered a behind-the-scenes look of her zombie-filled video for 'Sleepwalker.' The zombies come to life in this clip, and Bonnie goes to work battling them.

We've gotta say -- the makeup artists and special effects artisans on this shoot were top to the notch.

McKee also shared the key points and inspiration about the actual video, too, offering an even deeper look.

"I wrote 'Sleepwalker' years ago when I was really down and out, and kinda tucked it away and forgot about it," McKee told PopCrush. "Then, last year, I was at the Korean spa with my girlfriends and one of them mentioned she was leaving to watch a marathon of 'The Hills,' and it made me remember the song. They left me by myself at the spa and it was really late at night... there were all these little old naked ladies with eerie beauty masks on, kind of laughing and looking at me, speaking Korean, and I was standing there naked and suddenly felt very anxious and exposed."

She continued, "I imagined them conspiring against me and chasing me up the stairs in their scary beauty masks, and then it turned into a whole horror movie plot in my imagination and with 'Sleepwalker' fresh in my head, I automatically thought 'Zombies.' Originally, I thought a spa would be a really interesting location for a horror video, then you could get a sexy shower scene in there like the opening of 'Carrie.'

"But it was too complicated to shoot there so I opted for party house instead. That was the unlikely hatching of the concept for the 'Sleepwalker' video. You never know when inspiration will strike!"

The video was inspired by her favorite kitschy '80s horror flicks, like 'Return of the Living Dead' and 'Friday the 13th' (hello, hockey sticks, which are a subtle nod to that mask-wearing beast known as Jason Vorhees), and of course to Michael Jackson's 'Thriller.' She's a huge horror fan and it shows.

What about smooching her female co-star? Ain't no thang.

McKee said, "I was nervous about the kiss with Kelsey -- I didn't want her to feel uncomfortable at all, and I wanted to make it a good one! So I popped a bunch of Altoids and practiced dramatic kisses with my zombie boyfriend on set. Kissing Kelsey was the easy (and fun) part. The weird part was doing it in front of a whole crew of people staring at us! She was a really good sport about it. She was an awesome, fearless co-star!"

McKee, also an accomplished songwriter who has worked with everyone from Katy Perry to Britney Spears, said, "The last scene we shot was of us up on the hill overlooking a burning Los Angeles. We did a great job at looking miserable, because we WERE miserable!! It was the end of a 15-hour day, I had fallen down the stairs at least three times escaping zombies, and it was the middle of winter on a super cold windy night on the edge of a cliff. We were FREEZING our asses off and in between cuts would have to hold each other for warmth and huddle with the hair and makeup team!"

The singer also revealed that the photos in the opening monologue of the actual video were "taken at an abandoned amusement park that was destroyed by Hurricane Katrina. We used PhotoShop to make them look like it was nighttime, and make them even creepier than they already were. They made for an excellent zombie apocalypse backdrop!"

Watch the 'Sleepwalker' video here.