Tom Hollander has admitted it was "very challenging" filming 'Us' in four different countries, and there was "a lot of stress involved".
Tom Hollander, Saskia Reeves and Tom Taylor in Us
The 'Night Manager' actor stars as Douglas Petersen - who plans a big European tour with his wife and son, to try to save their marriage - in the new Sunday night BBC drama, and he recalls feeling "quite pressured" because there was so much to shoot "in a particularly finite amount of time".
He said: "It was very challenging for production and shooting in four different countries.
"There were four different crews and we were shooting out of sequence as ever; so you could be walking into a doorway in Amsterdam in episode two, which then turned into a staircase in Paris in episode one, which turned into a bedroom and then weeks later back into a studio in London, to play the room through the doorway in Amsterdam, to enable you to end up on a different street in Paris.
"It was quite a logistical feat to get it done! There was a lot of stress involved but relief every time when you looked up at the amazing places you got to film in.
"We were also filming on the Eurostar and other trains, travelling from Paris to Barcelona but pretending that it was Paris to Amsterdam, which worked well until we got to the wilds of Southern France and Northern Spain where it didn't really look like the lowlands of Flanders!
"I remember feeling quite pressured because we had a lot of material to shoot in a particularly finite amount of time because of the length of the moving train journey."
However, Tom also admitted it was "magical" being able to film in special parts of Amsterdam, Paris and Barcelona without anyone else there.
He added: "It was wonderful to be shooting in the actual places.
"It was particularly magical as we had access to the Rijksmuseum in Amsterdam, a couple of rooms in the Louvre in Paris for an afternoon, the glorious Joan Miro Fundacion in Barcelona for a day and in our very own National Gallery.
"These all felt like a great privilege and it was magical because there wasn't anyone else in them."
'Us' has been written by David Nicholls, adapted from his own novel of the same name, and also stars Luther's Saskia Reeves and 'Doctor Foster' actor Tom Taylor as Doug's wife Connie and son Albie respectively.