Garth Davis' Lion is a multi-tasker. It's an Oscar-baiting tearjerker, a stranger-than-fiction true story, and the greatest ad for Google Earth the world will ever see.

Oscar nominee Dev Patel and eight-year-old Sunny Pawer both play Saroo Brierley, who at age five wandered onto a train that took him a thousand miles away from his small Indian village. Eventually adopted from a Calcutta orphanage, he is placed with a married couple in Australia and raised in a loving household. The identity and whereabouts of his Indian family seem like an unsolvable mystery - until, that is, the invention of Google Earth. Decades after that train ride, Saroo now has the tools to track his journey and potentially find his family.

Davis has found an irresistible ray of sunshine in Sunny Pawer, whose adorable smile and charisma would inspire maternal instinct in a Venus flytrap. Scenes of his arrival in Calcutta are shot with an intimidatingly frenetic energy, evoking Saroo's disconcertion and fear. The dangers facing homeless children in India are chilling, making the warm embrace of his adoptive parents (Nicole Kidman and David Wenham) even more heartwarming.

As the film jumps forward in time, however, the narrative stumbles. Patel's performance is beautifully nuanced, evoking Saroo's internal struggle as he transforms from a happy and outgoing character into someone tormented by the loss of his biological family. Unfortunately, clumsy writing and awkward flash-forwards unwittingly indicate that Saroo had actually never thought of his Indian family in 20 years, only to end up being obsessed, which proves bemusing.

Endless scenes of Patel frowning at a laptop screen also prove decidedly uncinematic, and awareness of the story's tear-jerking happy ending erases any potential for tension.

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