When "Doctor Who" star Karen Gillen was initially cast as Nebula in "Guardians of the Galaxy," she did something she later called "crazy": she shaved her head. The actress -- who is recognizable for her long red locks -- ditched her signature hair in order to play Thanos' daughter, who rocks a bald head. Heading into "Guardians of the Galaxy Vol. 2," she made a move that was only half as crazy.

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“I shaved half of my head this time, but they took away the butt -- like, the underneath-half of my hair, and then left the top part. That was the best gift ever,” she revealed to TheWrap.

She also went on to discuss her character's role in the sequel film, saying, "What I love about the second movie for Nebula in particular is that we get -- We know that she’s a pretty angry woman with some daddy issues. [But] in the second movie, we’re going to start to see how much pain her father actually caused her, and we’re going to delve right into the relationship with her sister Gamora.”

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“I think we might even feel a tinge of sympathy towards Nebula this time, because we really start to see the emotional crack in her character,” she added. “I was just allowed to completely explore that and take it to a completely different dimension with her. I was really happy about that.”

In the first "Guardians of the Galaxy" film, Nebula acted as Thanos' -- and then Ronan's -- right hand woman. As a daughter of Thanos, Nebula is a deadly assassin, and she was assigned to help Ronan find an Infinity Stone when Gamora went rogue. However, save for a fight scene or two, the two "sisters" never really interacted. Now that Ronan has been defeated and Nebula went her own way in order to save her life, it looks as though "Guardians of the Galaxy Vol. 2" will explore Nebula's relationship with her sister.

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Opening May 5, 2017, “Guardians of the Galaxy Vol. 2” is directed by James Gunn and stars Chris Pratt, Zoe Saldana, Dave Bautista, Vin Diesel, Bradley Cooper, Michael Rooker, Karen Gillan, Glenn Close, Pom Klementieff, Elizabeth Debicki and Kurt Russell.