The duo portray Dr Michael Morbius – a scientist who accidentally acquires vampire bat superpowers – and his fiancée Martine Barncroft in the latest entry to Sony's Spider-Man Universe.
Chatting exclusively to Digital Spy, the Puerto Rican actress weighed in on her Oscar-winning screen partner's unique mindset at work.
"We had a conversation before the movie started. He works in a very specific way. He likes the transformative aspect of acting, so we didn't really have to work on it," she told us.
"I did my homework and he did his homework and when we showed up, we had a silver lining right in the middle which was Daniel [Espinosa, director] guiding us both to not be in two completely different movies, but when we showed up, it was all there.
"We had a good skeleton to come out of which was our script, so we didn't talk about it as much. We just immersed ourselves in the world and that relationship was engraved in it. I felt comfortable enough to go there with him."
Further into our conversation, 6 Underground star Arjona also discussed the experience of working on a comic book blockbuster – specifically what surprised her.
"I think the surprise was more when I watched the film. Daniel does such a good job of making everything tangible.
"On the sets, I could open any drawer and there were things inside, it really felt like we were in a lab and that helped me, and I'm pretty sure it helped Jared as well, feel grounded in the space," she said.
"When I watched the movie, the special effects blew me away. You can only imagine so far and Daniel was good to show us the specs of what it was going to look like, but it was an early version. So when I watched the movie, I was so impressed with the outcome."
Morbius is released in UK cinemas this Friday (March 31), while US fans get the chance to see it the day after.