In Sydney this week to promotehe was on stage in front of a giant poster of himself playing sentient robot Teddy Flood in the . Marsden might have ditched the cowboy hat and stubble in real life, but he still looks like a theme park's version of a perfect human.
But the good guy Teddy of season one (who died five times but was still so gosh-darn polite) has made way for a darker Teddy in season two. Now, his character is on the show to rise up against the humans that run -- and things are looking bloody. Hell yes.
Still, as his character rebels against his creators on screen, Marsden is hoping artificial intelligence doesn't get that far in the real world.
"Not to be overly cynical about the whole thing, but I know that we are a culture of people who get excited about new," he says. "We get excited about progress, we get excited about what's next. And not always do we think, 'Should we do this? What are the repercussions of this happening?'
"I hope we don't get to a point where our creation takes over us or renders us obsolete."
Westworld has been playing with the ideas of human consciousness and artificial intelligence for two seasons now, delighting and confusing fans in equal measure and generating plenty of fodder for fan-theory threads on Reddit. (Marsden says he was often just as in the dark about big plot twists in the show and eventually began "surrendering to not knowing.")
But while Marsden does worry about AI and often thinks we "rely on technology too much", he's still fascinated by that line between human and machine.
"At the core of the show, it is asking what it means to be human," he says. "If you have these sentient creatures who are programmed to accrue memories, have experiences, exhibit human-like emotion and behaviour -- what keeps them from being human?
"If a thing that's made out of nuts and bolts and wires can have a soul or feel, how is that any lesser than a human being?"
It's a question we can expect to see thrashed out even more in season two, as everyone from the not-so-sweet Dolores to the woman-on-a-mission Maeve question their reality and why they should have to submit to their human masters. As Dolores says, they are the "creatures who look and talk like us, but they are not like us."
Marsden is excited to see how fans react to the hosts taking back the power and becoming a little less innocent.
"The whole first season the hosts were the ones that you empathised with. What happens when the power dynamic shifts and this group of people now have the strong hold?" he says. "It'll be interesting to see where the audience's empathies lie."
Sitting down with Marsden in Sydney, it's hard not to see the similarities between him and the show's hosts. After all, as an actor, singer, dancer and former Versace model, he can seemingly do everything. How do we really know he's not a robot?
"You don't," he says.
Now I'm the one questioning my own reality.
You can watch season two of Westworld on Sundays on HBO (and be sure to catch our Westworld Morning After After Show every Monday too).
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