She's a Hollywood A-lister, with a mantelpiece groaning under the weight of awards. But Cate Blanchett has taken an unexpected diversion from her day job - to immerse herself in the world of the humble seed.
Her eyes light up as she enthuses about the banksia species from her native Australia.
"It's quite a brutal looking seed pod that only releases its seed in extremely high temperatures," she tells us.
"It does look like a cross between a mallet and a toilet brush. So they're not always pretty, but yet what comes out of them is so spectacular."
We meet her at Kew's Millennium Seed Bank (MSB) at Wakehurst botanic garden in Sussex. She lives locally and teamed up with the project as it celebrates its 25th anniversary.
"Really, I stumbled upon Wakehurst. I was just in awe of the landscape and I always feel regenerated by being in the natural world," she says.
"And then I discovered the seed bank, and I literally had my mind blown by the work that goes on here… and I thought, anything I can do to be connected to it - I found it so inspiring."
The MSB is home to more than 2.5 billion seeds collected from 40,000 wild plant species around the world.
The seeds, which come in every shape, size and colour, are carefully processed, dried and then stored in freezers at a chilly -20C.
The conservation project was opened by The King - then the Prince of Wales - in 2000. He's taken part in a special episode of a Kew podcast about the project called Unearthed: The Need For Seeds with Cate Blanchett.
In the recording he talks about his concerns that many plant species are being lost.
"I know how absolutely critical it all is, and the destruction of rainforests, the extinction of endless species, which have very likely remarkable properties," he tells the podcast.
When the seed bank first opened, it was seen as a doomsday vault - a back-up store of seeds to safeguard wild plants from extinction.
But 25 years on, the collection is being used for a different purpose: to restore environments that are under threat.
