It is at times gripping, tense, funny and joyful but equally there were times when I was impatient for it to move on
There was a moment after the first of two intervals during Fanny & Alexander at the Old Vic when I felt myself sit up straight. Up until that point the play had been entertaining but suddenly it got interesting as well.
Now there is nothing wrong with entertaining - it can be an overlooked element of theatre - but when you've got a play with a running time of 3 hours 45 minutes (when I saw it, it's since had 15 minutes trimmed away) entertaining isn't quite enough.
The Ingmar Bergman film, from which this has been adapted by Stephen Beresford, was also a bit of a beast in its running time - just over three hours - but I've not seen it so the story was a surprise.
Fanny and Alexander are young siblings growing up in a bohemian apartment block. Their parents Emilie (Catherine Walker) and Oscar (Sargon Yelda) are actors who run a successful theatre.
The children take parts in their parents plays and it is a sociable, creative and free upbringing among their extended family and friends.
It is a childhood full of stories, play and fun, despite the various tensions between the adults.
Oscar has a vivid if sometimes macabre imagination - he 'sees' and talks to the grim reaper. Is he just a worrier or is there something more fatalistic about his visions of death?
The latter would appear true when his father Oscar dies suddenly and, still grieving, Emilie, marries Edvard (Kevin Doyle) a widowed bishop.
This was the moment that I sat up. The hour or so up to the first interval is like watching a colourful, animated toy box with its set of ornate furniture and rich, red theatrical drapes.
When Emilie moves with the children into Edvard's home, the set is stark, the box has been stripped bare and painted white. It reflects the austere, strict, authoritarian style of parenting that Edvard employs.