ET has an early look at the emotional role Jennifer Garner took on right after she split from Ben Affleck.

In the faith-based movie, Miracles From Heaven, Garner stars as Christy, a mom who becomes a ferocious advocate for her 10-year-old daughter Anna (Kylie Rogers) when she is diagnosed with a rare, incurable disease. Their lives are forever changed when an extraordinary medical miracle unfolds, leaving specialists baffled and a community inspired.

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The film, also starring Queen Latifah and Martin Henderson (Everest), is based on the best-selling book by Christy Beam, who believes her daughter went to heaven after falling and was miraculously cured of her disorder.

The 13-year-old on which the story is based, Annabel Beam, now has no symptoms and is not on any medication.

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Miracles follows the massive success of another faith-based film, Heaven Is for Real, which took in more than $100 million worldwide.

Miracles From Heaven opens March 18, 2016.