There’s a generation who never got to experience the pure joy of a birthday at McDonald’s. So, we set out to fix that by throwing a party for Grimace — a character as beloved as he is goofy. The centerpiece of the celebration was Grimace’s Birthday Shake, a mystery flavored purple shake that we convinced McDonald’s to make and add to the menu nationwide for the occasion.

Every detail of Grimace’s party was designed to encourage party participation. Grimace took over McDonald’s social handles to invite the entire country. Guests could text the birthday boy, add to a collaborative party Spotify playlist, compete for the high score in a retro inspired “Grimace’s Birthday” videogame, turn their tongue into Grimace with a Snapchat filter, and much more.

The results surpassed our wildest expectations. The world created fan art, declared Grimace a queer icon, supplied social media with endless Grimace memes, and almost every publication from Complex to Better Homes and Gardens covered the event. But when one party guest posted a TikTok of himself trying the shake and meeting a gruesome end, suddenly the new Grimace Shake trend was all the internet could talk about — with 160,000 #GrimaceShake videos on TikTok and 9.7 BILLION impressions.

The mania resulted in a party foul…us breaking McDonald’s supply chain and running out of milkshakes before the campaign ended. Happy Birthday, Grimace!

Results:

• +2.8% 18-24YO Penetration vs same period year prior

• +40% Incremental Sales vs. projection

• +67% Meals/ Shakes Sold above high end estimate

• $5.65 ROMI, 19% from Earned Media

• 1.27M social mentions, 9.7B impressions

• 160k Grimace Shake TikToks w/ 4B views

• 100x Earned Social Volume vs projections