There's never smoke without fire.

Loosely based on a rumour that Princesses Elizabeth and Margaret snuck out from their sheltered lives to join the party on V.E. Day 70 years ago, A Royal Night Out charts the whereabouts of the sisters as they navigate the night in both restrain and frolic. Starring relative newcomers Sarah Gadon and Bel Powley as Princess Elizabeth and Princess Margaret respectively, veterans Rupert Everett and Emily Watson join the cast as the king and queen. While the standard slapstick gags and exclusively crafted Swarovski jewels appear in this coming-of-age film, what struck us was how fondly we took to Margaret.

Bel Powley

While Elizabeth is usually the princess to talk about, we found our loyalties lying with the other sister instead. P2's ('Princess Two', a term her highness coined herself) joie de vivre was adoringly captured by Powley's performance, which made for most of the movie's charm.

A Royal Night out

Bel Powley as Princess Margaret

Of course, we all know what becomes of her real life beyond the movie's reel innocence — a princess who enjoyed socialising with the jet set, Margaret was often seen at clubs and parties. Commonly known as the black sheep of the Royal Family, the press often dissected her failed romances and rumoured affairs.

Earlier this month, even at 13 years after her passing, an alleged affair with Peter O'Toole resurfaced in a biography of the Irish actor; which is exactly why this light-hearted comedy couldn't have come at a better time.

Here's the princess in all her post-war, pre-adulthood zest. Watch a preview below. 

A Royal Night Out opens tonight in local theatres.