Prom is a pivotal moment in every high schooler’s life. For Ruby Gillman (voiced by To All the Boys’ Lana Condor) and her friends, the plan was to pivot away from prom night entirely and enjoy a group hang instead. Shunning the formalwear rite of passage also meant Ruby could obey her mum’s rule of staying away from the ocean. A school dance on a boat would mean sailing dangerously close to the line she must never cross and Ruby determines to stay on dry land.

But teens are contrary creatures and as Ruby’s friends pair off it becomes increasingly obvious that the lure of prom is too strong to resist. And Ruby’s crush on fellow mathlete and effortlessly cool skateboarder Connor (Jaboukie Young-White) is compelling her to don a cute gown and follow the crowd…

Ruby’s parents are divided on how much freedom to give their girl. Dad Arthur (Colman Domingo) is an optimist who errs on the side of everything will be cool but mum Agatha (Toni Collette) has good reason and personal experience leading her to fear for Ruby’s future. The family always attributed their singular looks to ‘Canadian’ roots when impertinent questions were asked, however, the truth is that they are all Krakens and the women of their bloodline have an even bigger secret to conceal.

The reality of her heritage forces its way into Ruby’s day when a moment of bravery hurls her into deep water. Standing out from the crowd is the fear of every shy adolescent so her sudden transformation into a giant purple Kraken who smashes everything in her wake is, like, a total nightmare! Fortunately, Ruby gains support from some very unexpected sources; her mum is understanding about the Hulking out, the school’s cool new girl (Annie Murphy) wants to be her bestie and her long lost Grandmamah (Jane Fonda) is a literal queen. Princess Ruby is going to live happily ever after. Right?!

Ruby Gillman, Teenage Kraken is a peculiar beast; being rather charming with a brightly coloured, effervescent energy that makes it impossible to dislike yet a flimsiness which also makes it hard to fully engage with. This is partially because the narrative is familiar – this is essentially Turning Red with a tentacular twist – but also due to a strange haste in the first third that at times makes it feel less like a movie and more like an extended intro to a new series.

Which is not necessarily a bad thing. Ruby is Dreamworks’ first feature to centre a female character and the fish-out-of-water fun that writers Pam Brady, Brian C. Brown & Elliott DiGuiseppi manage to have combining the awkwardness of navigating a first crush with the horror of being different does lead to moments of genuine delight. Ruby has a diverse and loveably weird group of friends, it would be nice to get to know them more than the tidy 90-minute runtime allows.

As Ruby learns her true destiny and hones her warrior skills beneath the waves, the jaunty and tactile animation of her landlocked life becomes more ethereal and we are drawn into a mermazing coming-of-age story that will enchant young audiences. The stakes are never very high and the more jaded among us might find our minds wandering but for tween girls in particular this sweet adventure contains valuable messages about learning to love yourself just as you are and models healthy relationships.

A twist in the tale leads to a Kaiju clash, demanding a family reunion before it can resolve and the Monster High-esque baddie is perhaps the weakest point of an otherwise attractive and surprisingly entertaining film. Yes, it’s fluffy, fails to build upon family bonds and borrows heavily from Descendants 2 (a classic!) but Ruby Gillman, Teenage Kraken boasts a strong vocal cast, a lovely fizzy soundtrack and a story that successfully centres a girl without diminishing the action. We would like to see what Ruby does next.

Ruby Gillman, Teenage Kraken is in cinemas June 30th