plans to give Anna a surprise birthday party with the help of Kristoff, Sven, and Olaf; but while Anna is led on a party treasure hunt by a string that winds through the kingdom, Elsa has caught a cold, and unknowingly produces a group of "Snowgies" with each sneeze, who begin to dismantle the birthday party's decorations while Kristoff tries to stop them. While Elsa takes Anna on the hunt, Kristoff, Sven, and Olaf try to control the snowmen and fix the decorations in time for Anna and Elsa's return. Meanwhile, Elsa's condition rapidly worsens and she becomes delirious with fever. After Elsa nearly falls off a clock tower, Anna convinces her to rest. They walk back to the castle where Elsa apologizes to Anna for "ruining" another birthday, but Anna reassures her that she didn't ruin anything. As Anna goes to lead Elsa to bed, the doors to the castle open to reveal Kristoff, Olaf, Sven, and a mountain of tiny snowmen, who surprise Anna. Elsa sneezes again and finally sees more tiny snowmen that she produced. Despite Anna's protests, Elsa concludes the party by blowing into an alphorn. However, she sneezes into the horn, forming a giant snowball that inadvertently hits Hans overseas. Elsa rests in bed under Anna's care while she points out that taking care of her beloved big sister is the best birthday present ever. Olaf, Kristoff, and Sven escort the small snowmen to Elsa's ice palace, where they stay with her snow-giant doorkeeper Marshmallow.
On September 2, 2014, during the ABC airing of , Walt Disney Animation Studios' chief creative officerJohn Lasseter announced that a Frozen short film with a new song would be released in the future. On the same day, Variety announced that the short would be released in early 2015 under the title Frozen Fever, with Chris Buck and Jennifer Lee returning as co-directors, Peter Del Vecho returning as producer and a new song by Kristen Anderson-Lopez and Robert Lopez. Olaf the snowman would also make an appearance in the short. On December 3, 2014, it was announced that Aimee Scribner would be a co-producer and that Frozen Fever would debut in theaters alongside Walt Disney Pictures' Cinderella on March 13, 2015. In late December, the co-directors told the Associated Press "There is something magic about these characters and this cast and this music. Hopefully, the audiences will enjoy the short we're doing, but we felt it again. It was really fun." Around the same time, Dave Metzger, who worked on the orchestration for Frozen, disclosed he was already at work on Frozen Fever. The short features the song "Making Today a Perfect Day", by Anderson-Lopez and Lopez. At the premiere of Cinderella and Frozen Fever at the El Capitan Theatre in Hollywood, California, on March 1, 2015, Josh Gad told USA Today, "I want to apologize to parents everywhere for the fact that children are going to be singing a whole new Frozen song" The creators started brainstorming possibilities for the short film in June 2014. After early discussions about Olaf, head story artist Marc Smith pitched the idea of what might happen if Elsa had a cold, which became the basis for the short's plot. The directors began working on the short in June and by August were back in the recording studio with the cast to lay down vocal tracks. The production of Frozen Fever took six months. All of the animators from Frozen wanted to come back to animate at least one shot on Frozen Fever, resulting in a large number of animator credits for a short film. They struggled to squeeze the animation phase of the short's production into a tight time slot in fall 2014 after animation wrapped on Big Hero 6 and before the studio's animators had to start working on subsequent features. It was during this time period that the directors began to realize how much they missed the Frozen characters; they began to discuss the ideas that evolved into a full-length sequel, Frozen II.
Release and reception
Frozen Fever premiered in theaters alongside Walt Disney Pictures' Cinderella on March 13, 2015. It was released on Digital HD and Disney Movies Anywhere on August 11, 2015, and was released on the Walt Disney Animation StudiosShort Films Collection DVD/Blu-ray Combo Pack on August 18, 2015. It was also included on the Blu-ray, DVD, and digital HD releases of Cinderella on September 15, 2015. On November 9, 2015, it was released on an exclusive DVD copy of its own, courtesy of Tesco stores across the UK. USA Todays Claudia Puig rated the short three stars out of four, and described the new song as "pleasant". She concluded that although the short "is not as exhilarating and inventive as the original, it's still a treat to see an abridged tale of these two sisters in a warmhearted spinoff." Writing for BBC, Natalie Jamieson called the new song "catchy and fun". Dan Kois of the Slate called the film "a real bummer, the first recent misfire from Disney's shorts program, and thus the first serious misfire from the Lasseter-led Disney." The Daily Telegraphs Robbie Collin praised the song "Making Today a Perfect Day", stating that "it's a lip-smacking confection, dusted with pure icing sugar, and suggests that songwriters Kristen Anderson-Lopez and Robert Lopez are capable of coming up with something special for the forthcoming feature-length Frozen sequel." CraveOnline's Witney Seibold wrote that the film "is a celebration of the very kind of conspicuous consumerism that Disney is always smearing the landscape with." Mike Scott of The Times-Picayune wrote that "with its blend of sweetness, silliness and tunefullness, this animated Disney short is satisfyingly consistent in vision and in spirit with the original Frozen."
