The Umbrella Academy stars thought shock season 4 romance twist "was a joke"

Episode 5 of the new season, titled Six Years, Five Months, and Two Days, sees Lila, who is married to Diego (David Castañeda), strike up an unlikely romance with his brother Five after the pair get stuck in the waypoint between timelines (or the subway system).

After hopping from timeline to timeline for years, they settle down in one and eventually form a relationship, before Five finds a way back.

Understandably, the actors were stunned by the development, with Arya exclusively telling RadioTimes.com: "I'm not sure if I should really say this, but one of the writers accidentally told me that that was going to happen at the premiere last season, and I thought that they were joking.

"I literally laughed, and I was like, 'Haha,' and then when I read the script, I was like, 'Oh, they weren’t joking!'"

Gallagher responded: "I had a similar reaction. Well, at first it's, like, just fully unexpected, because the characters always seem at odds with each other. But it sort of flipped like a magnet at a certain point. I was like, 'Oh, that actually makes a lot of sense, personality-wise.'"

Arya went on: "Then I started thinking about the seasons before, like, they always knew this was gonna happen!"

With Gallagher asking, "Do you think they actually knew that many seasons before?" Arya pointed out, "I think so, they know what they're doing."

Over to showrunner Steve Blackman! He told us: "I sat with the writers and we said, 'What would happen if you spent seven years with someone and were starting to give up ever coming home?'

"I mean, some of it speaks to the domestic problems between Lila and Diego. And part of it has to do with that, as much as Five and Lila would hate to say it, they're very similar.

"They've been fighting so hard all these seasons, but alone, they realised they have a lot in common. They're very similar people.

"I wonder what the fans will make of that moment. But I think it's an earned moment. Because, remember, it's not a few days - they’ve been together now trying to stay alive for seven years. And I thought it was a great moment."

As for whether fans will agree, only time will tell.

The Umbrella Academy seasons 1-4 are streaming now on Netflix.

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