Former Friends star Jen was seen shooting scenes for the flick alongside Sam Worthington in Los Angeles, California on Monday (7 April).
As we previously reported, the role sees Jennifer going through somewhat of a makeunder, sporting a dark brown bob, minimal make-up and baggy clothing – a definite change from the blonde locks, flawless face and slinky dresses she favours on the red carpet.
Her character also has a large scar down her face.
Jennifer plays a grieving mother struggling to cope with the loss of a child and who becomes intrigued by the suicide of a young woman in her chronic pain support group.
As well as starring in the gritty drama, Jennifer is also listed as a producer.
Jen recently spoke to The AP about her career plans for the future, saying: "I just want to keep trying to surprise myself and I want to keep challenging myself and have the courage to really do that, in spite of possible failure."
As for how she keeps grounded amid all the interest in her life, she said: "You just have to work really hard to tune out the noise and the static. Because it gets louder, and people really have an opinion, and you don't want to shy away from taking chances for fear of what people will say, or living in the wreckage of the future (of) what may be if I do this."
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