Jake Gyllenhaal said it was the “alchemy” he has with his co-star that drew him back to the West End for the first time in 18 years.

The Oscar nominee, who celebrates his 39th birthday on Thursday, last trod the boards in the UK in 2002 in Kenneth Lonergan’s play This Is Our Youth.

He will star opposite Annaleigh Ashford as the French post-Impressionist painter Georges Seurat in Sunday In The Park With George, which follows the painter as he completes his most famous work, A Sunday Afternoon On The Island Of La Grande Jatte.

Gyllenhaal first appeared in the musical by Stephen Sondheim and James Lapine at New York’s City Centre in 2016, before transferring to the Hudson Theatre on Broadway in 2017.

He said he and Ashford had to reunite on stage because there is “no other combination” that could recreate what they achieved in the US.

He told the PA news agency: “We only had 10 weeks to do it because we could fit it within that period of time. It always felt unfinished.

“To us, I think, to me at least, there is no other combination within this production.

“The special thing about this show is that there is something about the alchemy of these two characters – about the love story between the two of them.

“I don’t think you can switch that up and get the right thing again, in my opinion, and so we had a lot of things that were unfinished and we wanted to finish them up.

“We have come to the best place to do that, to London, to do it together again.”

Asked whether they plan to make any adjustments to the play, Gyllenhaal added: “There’s not much to change about a masterpiece, in this production. You have to just keep digging at it.

“We kept it very simple from the beginning because we knew that it would be all about the music and the lyrics and the storytelling. And that’s what is special about the show.

“We will have new cast members in some of the roles, and there are things that we have wanted to dig deeper into, particularly in their relationship.

“These characters have such a profound relationship to each other that spans over time, decades, and comes back again.

“For me, digging deeper into the love and heartbreak that these two experienced together is our real interest.”

Previews of Sunday In The Park With George will begin at London’s Savoy Theatre on June 11 next year and the show runs until September 5.

Tickets are on sale now.