The Duke and Duchess of Sussex received a standing ovation as they made one of their final appearances as working royals, as they attend the Mountbatten Festival of Music.
Prince Harry and Meghan are the only senior royals at the event at the Royal Albert Hall on Saturday evening.
It comes ahead of their Commonwealth Day Service appearance, when they will be publicly reunited with Prince William and Kate, as well as the Queen, and Prince Charles and Camilla.
Prince Harry is attending in his capacity as Captain General of the Royal Marines.
The duchess wore a striking red floor length gown by Safiyaa to match her husband’s uniform, with red Aquazurra shoes, a Manolo Blahnik clutch and earrings by Simone Rocha.
The duke and duchess received a long round of applause and a standing ovation from the crowd in the Royal Albert Hall as they took their seats in the royal box.
The Sussexes have made a number of public and private engagements this month, two months after they announced they wanted to step back as senior members of the Royal Family.
They were in public together for the first time on 5 March, when they attended the Endeavour Fund awards, both giving out an award, and with Harry making a speech.
But all eyes will be on Monday’s event, when they will join the rest of The Firm for what could be the last engagement of its kind.
Although they do not officially step back until 31 March, there are no engagements planned beyond the 9 March.
As well as public engagements, the duchess has been making private visits while in the UK.
On Thursday, before the Endeavour Fund awards, she went to the National Theatre, where she is a royal patron, to visit the immersive storytelling studio.
Keeping the visit secret, she announced she had been on Friday, sharing pictures on Instagram, and writing: “The goal of this method of virtual reality is to enable us to better connect and empathise with each other as people, regardless of race, age or nationality.”
The post also confirmed the couple had recently been at Stanford University in California, looking at similar types of technology.
On Friday, she was seen at a school in Dagenham, east London.
The couple’s latest engagements have not been featuring on the court circular, which keeps track of the events royals attend.
The Mountbatten Festival brings together world-class musicians, composers and conductors of the Massed Bands of Her Majesty’s Royal Marines.
This year, the performance will mark the 75th anniversary of the end of the Second World War and the 80th anniversary of the formation of Britain’s Commandos.
Proceeds from the event go to the Royal Marines Association – The Royal Marines Charity and CLIC Sargent, who support cancer victims aged under 25 and their families.