It won't surprise the legion of fans who eagerly await the holiday campaign each year from Adam & Eve/DDB and U.K. department store John Lewis that "Monty's Christmas", the 2014 effort, won the Grand Prix for Creative Effectiveness.

In fact, the heartwarming tale of a boy and his penguin pal Monty earned the Film Craft Grand Prix at last year's Cannes Lions International Festival of Creativity (to set the bar high on creativity, Creative Effectiveness entries must have been at least shortlisted in a creative category at Cannes in a previous year).

But "Monty's Christmas" is much more than a spot you want to watch over and over (it got 32 million views). John Lewis also created an in-store experience featuring Monty, the penguin from the ad, in partnership with Samsung. And kids could see their own favorite toys animated in 3D using Microsoft scanning technology in "Monty's Magical Toy Machine" and interact with the characters from the ad in a virtual world with "Monty's Goggles," using Google Cardboard. There were also Monty-inspired store windows and a range of merchandise that sold out in three days. In one far-ranging effect, WWF penguin adoptions rose by 300%.

Why it won: "It honestly stands for everything the Cannes festival stands for," said jury president Andrew Robertson, CEO, BBDO. "It's beautiful, emotional work for a retail brand that was proven to have contributed to revenue growth of 132 million pounds."

The jury: Mr. Robertson led a nine-person jury that is almost half marketers; this year, from Citi, Korean Air, Telefonica Vivo and Visa. And, kudos to Cannes organizers, six of the nine judges were women.

Lions awarded: The Creative Effectiveness category saw a significant drop in entries, to 109 this year from 160 last year. Apart from the Grand Prix, the jury awarded just two gold, four silver and six bronze prizes.