The rise in Irish Republicanism. Tick.The decline of the aristocracy. TickThe persecution of gay men. Tick.
It is 1927, two years after the end of the action in the last series of the TV show, and the writer Julian Fellowes has a busy agenda.
The 52 shows over the six series run of the TV show afforded him the time to reflect the big stories of the day - be it the sinking of the Titanic, or the arrival of electricity.
But a two hour film in which the audience will want to see each of their favourite characters have a storyline, as well as appreciating the historical accuracy, demands the action move fast. And it does. From the start.
Perhaps too fast in places.
And yet the moment the luscious sound of John Lunn's theme music begins, I am lost in glorious, dreamy nostalgia.
Has it really been four years since the Crawleys bade farewell in a Christmas show that 10 million watched?
The show's fans are apparently the reason the shows makers decided to go for the big screen treatment.
In fact, the idea for a possible film had been in discussion since the fourth and fifth series of the show.
And the transition appears seamless because the TV series itself was so cinematic.
The film does not feel very different at all from the small screen version, and that is why it will be a huge hit.
It's adoring fans - the worldwide audience numbered around 120 million - simply want more of the same.
And that is what they get.
Wrapped around the story of a royal visit to the house, we see the characters continue lives that are familiar to us from the award winning TV show.
No one acts out of character - and that familiarity is the winning formula.
It is safe, and utterly compelling.
What we all wanted was the TV show back again.
We've got it, only on a bigger screen and two hours long instead of one.
The prospects of another film apparently rests on whether this one succeeds at the box office.
I strongly suspect the Crawleys and their household will be back.
And Dame Maggie Smith, as the Dowager Duchess, will do very well in awards season.
The film is set for release in the UK on Friday September 13.