It's lunchtime at the Royal Albert Hall and a stagehand is carefully calibrating the auditorium with a two-metre pole.
His job, ahead of the first night of the Proms, is to make sure the orchestra's seats are all the correct distance apart.
His meticulous measurements might seem comical - but the rules are being strictly enforced, even when the players are in place.
"They have this specially-made ruler and they come and they put it between us," says conductor Dalia Stasevska.
"And when the guy comes to the rehearsal room he sometimes has this suspicious look. Especially in the beginning, when people were moving their chairs a little bit, he was like, 'Don't do that'."
The social distancing is essential to ensure this summer's Proms season can go ahead. Over the next six weeks, the Royal Albert Hall will welcome more than 2,000 musicians, 30 orchestras and, crucially, tens of thousands of fans.
There won't be quite as many as in previous years - the stage has been expanded to allow the musicians to spread out, squeezing space in the hall - but up to 5,000 people will attend every night, a huge increase on last year's figure of zero.
"It's thrilling," says Stasevska. "We've been waiting over a year to have full audience. We're all going to play our hearts out."
With the Finnish conductor in charge of the BBC Symphony Orchestra and the BBC Singers, the first night promises to be a special occasion.
A colourful and popular figure, she breathes life into the music with her surprising-but-evocative directions. "Try playing with the rhythm of a sewing machine," she instructed the string section at rehearsals this week.
Friday's concert will open with Vaughan Williams' Serenade To Music, described as a "love letter to music and musicians" after a year of lockdown.
It will be followed by the world premiere of James MacMillan's wistful When Soft Voices Die; before closing with Sibelius' majestic second symphony.
Speaking on the final day of rehearsals, Stasevska told BBC News about her hopes for the concert, the challenges posed by the pandemic, and last year's row over the decision (later reversed) to drop the words of Rule, Britannia! During the Last Night of the Proms.
What's it like to be back in the Royal Albert Hall?
It feels amazing. I have a little bit of goosebumps!
What's the moment you're most looking forward to?
Just to hear the people clapping and the whole ritual at the start: The silence and the people waiting for the first note.
And the second one is the Sibelius symphony. We have been dreaming for the last year: What are going to perform first? What would be the biggest bang? And Sibelius Two is just the perfect piece.
You have a personal connection to Sibelius, isn't that right?
Yes, my mother-in-law is his granddaughter - but I have always felt a really strong connection to Sibelius, and performing this symphony on the first night is really important because it has so much hope, so much brightness.
He was in Italy when he composed parts of it, and it was for him a new beginning. He was searching for a new style, something more European. At the same time, it's very autobiographical and it goes into quite dark places - but how he comes out of it, with this celebratory finale is really wonderful. And this is just the right moment to perform it.
When you came back for your first rehearsal this year, did it take little while to find your groove?
Yes, it takes a bit of time - because we are still playing socially-distanced, and this is the first time we are playing a proper symphony in over a year. But there's excitement that we finally can make a lot of noise!
What are the precautions if someone in the orchestra tests positive or gets pinged?
It's the same as normal - if you get ill, you just have to do your time at home. It's no different for us than any other place where people are working.
You studied violin before you became conductor. Would you step in if the principal violinist fell ill?
Maybe not for the principal violin! But I love playing in the orchestra, and I actually dream that when I retire one day, I might find myself playing in a nice amateur orchestra in Tenerife.
On the beach with a drink in one hand…
Yes, in the sun and enjoying it!
You conducted the Last Night of the Proms last year, with a reduced orchestra and no audience. What was that like?
It was very different - but it was also very moving because many of us hadn't seen each other for almost six months.
There was controversy over the decision not to sing the words to Rule, Brittania and Land Of Hope And Glory… What did you make of it?
I've kind of moved forward from all of that. What I really want to say is that I'm extremely proud that the whole Last Night actually came together at all. The pandemic has been such a struggle for everyone and it was not clear that we could make a concert happen at all, and that's something to celebrate.
There were some incorrect reports that it had been your decision to scrap the lyrics. How did you feel about that?
Well, the media has it's way of telling stories and we have our own way to tell the story - through the music.
What role does music play in helping people heal after the last 18 months?
Classical music has always had a healing quality and music in general can express things that we can't verbalise. It's such a unique form of expressing what we feel, so I think music hasn't been ever so important as it is now.
After the Proms, you're booked to play all around the world. What are the challenges of an international career during the pandemic?
Well certain visas are very difficult to get and I've had to do 14 day hotel quarantines. That have been quite a challenging experience, to be in full isolation. And of course they make a difference in your schedule, so you can't do three concerts a month that easily. Sometimes you can only do one - so there's been a lot of adjustments.
Have you attended any concerts yourself? What was the atmosphere like?
I went to a rock festival two weeks ago on a Finnish archipelago and they let 1,500 people go - my husband was performing in one of the bands. It was so freeing, but I was also a bit scared. I listened to some of the bands backstage and then on the sides, but always with a mask on.
Has the last year changed the way you relate to music?
Yes and no. No in that music has always been my number one passion, and I feel I have a freedom onstage that I can't have otherwise. What has changed is that I've lost some of the stress I used to have playing with new orchestras or in the build-up to important concerts.
Now I'm just enjoying being able to be there at all. I haven't ever had so much of a smile on my face, every single day I've been able to work.
The First Night of the Proms takes place at the Royal Albert Hall on Friday 30 July. Coverage is on BBC Two and BBC Radio 3 from 20:00 BST.