The actor spoke with ET at the Tribeca Film Festival premiere of 'Blue Night' about how the diagnosis forced him to reflect on their relationship and their bond.
Common is opening up about how he dealt with his late father's cancer diagnosis, and how the tragic news led to meaningful self-reflection on their relationship.
ET caught up with the 46-year-old actor at the Tribeca Film Festival premiere of his new film, Blue Night, in which star Sarah Jessica Parker plays a New York jazz vocalist who receives a diagnosis that turns her life upside down, forcing her to reflect on her path through life.
According to Common, he had a similar experience when his father, Lonnie Lynn, was diagnosed with cancer.
"Looking at my life and my relationship with him, it made me feel my own, not only vulnerability but [the] feeling of, you know, 'I'm not invincible,'" he shared. "It was something that just made me look at my life and these things happen in life."
Common's father, whose spoken word poetry can be heard on several of his son's albums, died in September 2014, at the age of 71.
"I think faith is one of the things that gets us through," Common said. "And our loved ones, and that's what this movie is about."
Common also opened up about Parker's role as a Jazz singer in the emotional drama, which required her to show off her vocal skills in several scenes, and the "Glory" singer had nothing but praise for his co-star's talents in the recording booth.
"I didn't give her much advice. I told her she sounded good 'cause I supported her and it was the truth," Common recalled. "I just told her to stay free with it… jazz is free, expressive, and she's like a jazz singer. Man, she did it! She's got the 'it' factor."
With his role in Blue Night and upcoming roles in seven other films, Common's acting career is on fire right now, and the entertainer said he's looking forward to the opportunity to take on characters that he can lose himself in.
"I just want to do characters that really are meaningful and impactful," she shared. "I don't want to do characters [where] people think, 'Oh, that's Common.' I really want to, you know, dig into these characters and I want to do something like a Marvin Gaye story."
"I want to just go places as an actor that my favorite actors go," he continued. "I'm an actor and I'm growing, but I want to be a great one."
Blue Night -- also starring Renée Zellweger, Taylor Kinney and Simon Baker -- is due out later this year.
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