The Hit Return of Mars’ Unexpected Guests

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The last few years have seen Halloween become an advertising battleground, with Spooky Season themes and promotions ever-present on social media and traditional channels. The heart of the holiday remains candy, though, and Mars’ M&Ms brand have a tradition of silly, scary, and funny Halloween ads.

That also means they’ve got a successful back catalogue of ads ready to show again. Wear-out is a myth, and seasonal perennial ads (like the Hershey Kisses and Coca-Cola Trucks at Christmas) are a budget-friendly source of reliable effectiveness. If you’re a brand with high quality seasonal ad inventory, it’s never a mistake to re-use the best ones.

In 2024 M&Ms made a very special appearance in a Halloween ad, a collaboration with Snickers which acts as a double promotion for Halloween candy. The M&Ms spokescandies have gone trick or treating in costume themselves, to the confusion of the humans they visit who are handing out treat-size Snickers. The man points out that as giant candies the animated creatures may have more to fear at Halloween than most. The M&Ms make themselves scarce, Snickers in hand.

Officially “Unexpected Guests”, by BBDO, is a Snickers commercial, but of course it’s doing double duty as an M&Ms one too, and both brands are prominent. Which means both brands reap the benefits of its effectiveness, as the ad is back on screen this Spooky Season for a second go.

And it’s not lost any of its power to entertain. “Unexpected Guests” scores an exceptional 5.3-Stars, which puts it in the top 8% of all US candy ads. Candy is a popular and highly emotional category – at 3.7-Stars it has one of our highest norms in Test Your Ad. That means it’s even more important to make ads which entertain, delight and stand out from the crowd like this does.

The high scores and continued effectiveness of this ad raises the question of why there is such a turnover of new candy commercials every year. Given it’s a very tough category to truly excel in, why don’t more companies do what Mars is doing here and continue to run with the best ads they already have?

Sure, this is playing devil’s advocate a little – if you have campaigns as reliable, consistent and good as Snickers and M&Ms have had over the years, especially with the M&M spokescandies, why wouldn’t you make new ads? But we’ve long pointed out that chasing novelty over consistency is a high-risk, high-expense strategy for brands which is proven to not be as effective over time as investing in great work and great characters.

There’s no good reason for Mars not to run “Unexpected Guests” every year, since it’s an unusual and seasonal ad that boosts two brands with one spot. Halloween may be the time for unexpected guests, but it’s familiar presences that move the effectiveness needle.