SPOILER ALERT: Do not read if you have not yet watched the fourth episode of “Years and Years.”

Russell T. Davies’ limited series “Years and Years” began with a birth, but it did not wait until the finale to book-end the story with a death.

In the fourth episode of the multi-year spanning family drama, the Lyons family lost Daniel (Russell Tovey), who drowned while trying to cross back into the U.K. illegally with his boyfriend Viktor (Maxim Baldry).

“He’s arrogant and he’s heroic,” Tovey tells Variety. “Yes, it’s what you do for love in a desperate situation, but he’s very arrogant. He thinks, ‘People like me don’t die. We’re going to survive and I’m going to get the life I want, because that’s what I get.'”

Originally, Tovey says, Davies’ plan was for Viktor to be the one who didn’t make the journey. “I was like, ‘Oh s—, that’s awful,'” Tovey recalls, “but in my head I was thinking I could do a eulogy, have a big cry, do all of the acting stuff to be sad — this will definitely be the BAFTA!” But then Davies told him he changed his mind — because he was seeing too many real-life refugees dying on beaches. Tovey admits he was conflicted about the idea at first: “If I wasn’t in it, I would think it’s the best idea ever, but the fact that I’m in it, I think it’s a terrible idea!” Knowing he wasn’t missing out on a chance to be in a long-running series (Davies planned “Years and Years” to be a definitive one-season series from the start) helped soften the blow, though. As did the fact that the fourth episode proved “the key point of the whole show,” says Tovey.

“History seems to come in waves, and things like this have happened before, and you look at how people turn a blind eye. In Chechnya there is a gay concentration camp, and people are aware of it, but do people believe it and are denying it? It’s this mysterious thing that’s happening in some part of the world,” he explains. “And because Daniel died, it made people go, ‘That could happen to anyone.’ At some point this country, your country, could go crazy, and you have to get out. What stops you from getting on that boat?”

The couple first met in the series premiere, when Daniel, a housing officer, popped in on a refugee in one of the U.K.’s sanctuary developments. The guy he was looking for was not there, and he met Viktor instead, bonding over tales of what Viktor had been through in his home country, simply for being gay. When, at the end of that episode, Daniel thought he was going to die because Donald Trump launched a missile, he left his husband and family behind and ran to be with Viktor. That began their love story in earnest, but because of the show’s pace and fast-forwarding through time, most of their time together, especially those early days, was not seen on-screen.

“I guess he would have come back with his head bowed low, sort of coy, ‘Sorry guys, I don’t know what happened, it was a bit of madness. Can we just forget that, and by the way this is my new boyfriend,'” Tovey says. “I think his older brother would have been fine, but I think his sisters would have given him a hard time — especially Rosie: Rosie probably wouldn’t talk to him for awhile, taking it as personal hurt. But the thing about families is, you can say and do things and know you will be forgiven.”

Tovey admits that he works out deep backstory for his characters with every job he has, so his process to understand where Daniel had been wasn’t different. “In this case, the father and mother characters — as an audience you’re unsure if they’re going to appear, but we need to know they’re not. And you want to know what happened there and, as a family, where we went on holiday as kids, what school we all went to, did we all go to the same school? That’s conversations you have with the other actors: ‘This is how I fit, this is what I felt like,'” he says.

When things were no longer safe for Viktor in the U.K., he left, but Daniel never lost hope that they could be together. For a short time, the plan seemed to be that Daniel would live in Spain with him, but soon enough that was not a safe place, either. Through his sister Edith (Jessica Hynes), Daniel learned of someone who could help smuggle Viktor, and he went along with him. “At some point it’s, ‘I have to f—ing do this now because this is what I’ve told myself I’m doing. So I have to do it and we’re going to get an amazing story and have a life,'” Tovey says. “I have to do this, or what’s the point of the rest of my life?”

Even as things start to go south, such as Daniel having his passport stolen by a woman who claimed she would use it to make a fake for Viktor, his attitude never waned from wanting to cross with his boyfriend. “He was out of options,” Tovey admits, “but, ‘F— it, it’s going to be all right.'”

Of course, then the brutal irony is that he wasn’t. The overcrowded raft Daniel and Viktor were floating on hit rough water and capsized close enough to land that many, Viktor included, survived — but Daniel did not.

“It was an intense couple-day shoot. It was really freezing cold, and the water’s freezing, and it was really heavy because you’ve got all of these people on this boat and the reality of it. The opinions I had before are even more sympathetic and generous to people who do that now. And it’s happening every day — it’s happening all the time — people are desperately trying just to be alive,” Tovey says.

“Everyone’s really challenged in their opinion. They know Viktor and Daniel love each other and were really genuine, but then you’re like, ‘He did this all for you, and you’re alive!’ Would they have chosen him to die over Daniel? Maybe. Everyone’s conflicted in how they deal with the death of Daniel and their own personal prejudices.”

“Years and Years” airs Mondays at 9 p.m. on HBO.