The actress opened up to ET about her action-packed new film, which hits theaters on Jan. 31.
Blake Lively is getting dark and dangerous in her new thriller.
In The Rhythm Section, Lively is out for answers and revenge after losing everything she loves and then discovering it was no accident.
ET went behind the scenes of the tense international spy thriller and sat down with Lively to talk about her challenging role.
"In this film, my character, Stephanie, lost her family in a plane crash, [and] she falls into drugs to cope with the pain," Lively explained.
As it turns out, the crash wasn't a tragic accident. There was a bomb on board that caused the devastation and stole her family from her.
"She goes on a mission to find out who did it and why, and tries to avenge her family," Lively shared. "That's really what changes her."
The film allowed Lively to show off her action chops, and features some intense fight scenes and wild stunts. So wild, in fact, that production had to be halted for a month after Lively badly injured her hand and needed surgery.
However, the gritty, high-octane drama also gave the actress an opportunity to get steamy with her co-star, Sterling K. Brown, share serious screen time with Jude Law, and sport a variety of wildly different looks as her character goes undercover and in disguise on her quest for revenge.
The Rhythm Section hits theaters Jan. 31.
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