Octavia Spencer on "The Shape of Water," Guillermo del Toro and coming into her own

Academy Award-winning actress Octavia Spencer knew after reading the first scene of "The Shape of Water" that it would be "magical." She was also sure that she wanted to be a part of it.

Director Guillermo del Toro's latest film, which he also wrote and produced, is a fairy tale set in the 1960s about a mute woman who falls in love with a creature held captive in a government lab. Spencer's character tries to help her friend save the creature before he is dissected. 

"I'm a huge Guillermo del Toro fan. I've seen everything he's directed and just about everything he's executive produced and he's an auteur, a true auteur. The first scene when everything is underwater — I said 'Oh my God. They're gonna be doing things like this. I want to be a part of this movie,'" Spencer told "CBS This Morning."

Del Toro actually wrote the part for Spencer, but when the two first met to discuss the role, three hours passed by and they hadn't even gotten to the movie.  

"We talked about everything. Life, love, antiques, our love of antiques, dieting, I mean everything but the movie," she said.

For Spencer, an important part of the story is how it addresses the discrimination of the time – a theme that has relevance today.

"It's interesting because Guillermo is Latin American Canadian so he is also used to being considered 'the other,'" Spencer said. "He can address those political issues without pointing fingers. His two main characters can't speak so he uses marginalized people – a black female janitor, a closeted gay man in Richard Jenkins' character – to characterize the social mores of the day."

Despite Spencer's character being one of those "marginalized people," she holds a unique authority at the government lab where she works as a janitor. 

"Zelda is a woman of the times. It's 1962. Black people don't have the right to vote. So she's considered a second-class citizen within society but within her world at this facility, she's a queen. I mean she talks nonstop," Spencer said.

Her character's nonstop chatter also serves as the de facto voice for her mute friend and co-worker, Eliza, played by Sally Hawkins.

"It was a wonderful progression of friendship both in real life and on screen to get to play that opposite Sally," Spencer said.

Many have characterized the film as a love story for the romance between the sea creature and Eliza. It's also love that informed its title.

"'The Shape of Water' is the shape of love and love takes on the shape of the vessel. So if you are an ugly person, then the shape of your water going to be quite ugly, but if you're a loving person, you can see past the differences, and that's one of the beautiful things of the movie," Spencer said.

As for how Spencer is seeing herself these days, it's only getting better with age.

"In your 20s you really do spend your time wondering and caring about what other people think – and you should. And in your 30s you take a little ownership and start seeing yourself for who you are. And by your 40s – and I'm gonna say mid-40s, but the kind of latter end of it – I just I realize I don't have to care that much about what other people think because at the end of the day, if I'm being the best person that I can be, that's all I can offer and if it's not good enough, well then, honey, I'm not gonna lose any sleep over it." 

"The Shape of Water" opens in select theaters nationwide on Friday.