Catchy songs, one-liners from Olaf, an emotional, enchanting storyline; fear not, because Frozen 2 more than lives up to expectations. The stars of the animation sit down with Georgia Humphreys.

It's rare to watch a sequel and not be slightly disappointed.

Which is why fans have rightly been asking: How can Frozen 2 possibly be as good as the original?

Following its release in 2013 (yes, it really was that long ago), Frozen became the highest-grossing animated film of all time.

Even if you haven't watched it, you'll most definitely have heard its most famous song, Let It Go.

And you'll surely recognise its heroines, Queen Elsa (voiced by Idina Menzel), who was born with the magical ability to produce and manipulate ice and snow (powers she learned to control in the first film), and her younger sister Anna (Kristen Bell).

Menzel, 48, insists she had no fears about returning to the role.

That's because, the New Yorker says, she had complete trust in the creative team; director Chris Buck, and writer/director Jennifer Lee, who's also creative officer of Walt Disney Animation Studios.

"I do feel that they waited, and they were really patient about even having a sequel to begin with - which is unprecedented in a Disney film, musical film - and it's because they really wanted the right story to be told," notes the formidable performer, who became famous for Broadway musical Rent, before winning a Tony for her role as Elphaba in the show Wicked.

"They didn't just want to do a quick fix and send out a second movie, and I really respect that integrity that they had."

It was worth the wait. Set three years since the Snow Queen ascended the throne of Arendelle, all seems well in the kingdom.

But when an ethereal voice from the enchanted forest beckons Elsa to unlock the secret of a bedtime story she and Anna were told by their parents as children, the siblings - plus Olaf the snowman, iceman Kristoff and his reindeer Sven - embark on an adventure.

The thing Florida native Josh Gad, who voices Olaf, admits he was "terrified" of was the songs not living up to the hits of the first film.

But songwriters Bobby Lopez and Kristen Anderson-Lopez, who he has collaborated with not only for Frozen but also the Book Of Mormon, exceeded all his expectations.

"I think that the music is so brilliant, because it's not trying to repeat the songs in the first film," elaborates the actor and comedian, 38.

One rather hilarious - but also rather emotional - new tune is Lost In The Woods, in which reindeer-loving iceman Kristoff expresses his feelings about his relationship with Anna.

It's a much-anticipated moment for Jonathan Groff, who voices the loveable, bumbling character, to show off his singing skills (he didn't have a solo in the first film).

Sung in a dream sequence, it sort of feels like Kristoff is starring in a boyband video, complete with catchy harmonies and brilliantly cheesy moments.

"When I saw the animation for the first time, and I saw him do the lean up against the tree, I was like, 'Oh my god, I can't believe what they've done to animate the song'," quips Pennsylvania-born Groff, 34, with an excited grin.

"It was such a blast to record," continues the actor, also known for Netflix crime series Mindhunter.

"Bobby and Kristen wrote a phenomenal song and they talked to me a lot about really going for it emotionally, and being absolutely sincere, as those eighties ballads are. It's real emotion.

"And then to see how the animators all were in on the same joke, just taking it to the next level, was amazing to watch."

Meanwhile, the adorably witty Olaf is a scene-stealer once again, a highlight being his laugh-out-loud recap of Frozen 1.

Is it difficult not to laugh while in the recording booth?

"It's impossible!" retorts a lively Gad, who also starred as LeFou in the live-action adaptation of Disney's Beauty and the Beast.

"I mean, so much of my genuine laughter is in the film - that is our brilliant editor Jeff taking moments that actually happened in the booth and just shoving them into the film so that it feels real.

"I'm so grateful for the collaborative spirit of these films; our team trusts us so implicitly to take what they've given us, but also work within the boundaries of allowing some freedom. Not taking it too far but allowing us to really play."

As much as the sequel is a fun, uplifting Disney film, there's no denying it feels darker.

"It does, right?!" agrees Menzel. "I think they wanted to mature with the audience, too.

"You know, it's a couple of years later, the girls are more mature and evolving, asking deeper questions about the meanings of their lives."

On the same topic, Gad reasons thoughtfully: "Having seen it with many children, including my own, now, it is so reaffirming that they took the absolute right route, because while there are moments in it that are sad or challenging, kids love that - they love to be challenged.

"We loved it growing up; Lion King has some dark moments in it, and it's my favourite animated movie ever, probably. Bambi has a really dark moment in it, and it's an incredibly powerful movie. And I think that to run away from it... Kids will see through that. So, you need to embrace it."

One particularly memorable scene of Elsa's sees her talk about how fear can't be trusted.

Indeed, a continuing theme is "why people make the choices they do, and us confronting when we're acting out of fear vs love", explains filmmaker Lee, who's also worked as a writer on animations Wreck-It Ralph and Zootropolis.

"And Anna keeps showing us again and again - and all of the characters in this one - that love is the strongest way. All kinds of love."

Additionally, in Frozen 2, the idea of how we can fear change is also explored. Six years on from when we first met Elsa and Anna, does Menzel think these themes feel more relevant than ever?

She hesitates, contemplating her answer.

"I feel that often people in power use fear to keep people in their place, and keep the status quo," she suggests.

"And so, yes, I feel it's very relevant and, actually, a deep theme for this kind of film. But maybe (it's) something that we need to hear, and that we can't be afraid of change, and we have to take risks, and if we feel that calling in ourselves to do something different, to change the world, that we have to listen to that voice."

Frozen 2 is in cinemas now.