The Frozen short, which is titled Frozen Fever, takes place on Anna's (Kristen Bell) birthday, as her sister Elsa (Idina Menzel) attempts to throw Anna the perfect party - but finds her efforts complicated by various obstacles, including her own magical ice powers. A trailer has been released for the short (see above); and among other things, it teases an original song featured in Frozen Fever, from Frozen's Oscar-winning songwriters Kristen-Anderson Lopez and Robert Lopez.
Also returning behind the camera on Frozen Fever are Frozen co-director Chris Buck and co-director/screenwriter Jennifer Lee. Meanwhile, the voice cast will once again include Jonathan Groff voicing ice specialist (and Anna's love interest) Kristoff and Josh Gad as the lovable enchanted snowman Olaf. It remains to be seen if there are any other "guest stars" whose vocals make an appearance during the Frozen short (which takes place after the events of the 2013 movie).
Frozen Fever, by the look of it, seems as though it should make for a cute and pleasant return to the Frozen universe for fans of that Disney animated musical; it might well be better than the live-action feature that it will be attached to. If the short goes over well then who knows, the Mouse House might release additional Frozen shorts in the future, in lieu of the full-fledged sequel that may or may not happen one day.
Similarly, Frozen Fever doing well might motivate the Mouse House to release shorts for other recent animated hits, Wreck-It Ralph and Big Hero 6. The reported Wreck-It Ralph sequel is another project that might not be moving forward after all, while a Big Hero 6 sequel is not currently in the pipeline; which is to say, short films might be the best hope for those wanting to revisit those movies' worlds in the future. (And, from a creative perspective, that might for the better, anyway.)
Frozen Fever will premiere with Cinderella in theaters on March 13th, 2015.