Young adults who shed their body weight in tears at The Fault In Our Stars earlier this summer, will be similarly dehydrated by the conclusion of RJ Cutler's heart-tugging drama.

Based on Gayle Forman's bestselling novel, If I Stay centres on a talented teenager in limbo between life and death, who must choose between waking from her coma or skipping merrily towards the light.

How the heroine makes this choice isn't entirely clear.

Nothing happens when she whispers in the ear of her baby brother that she intends to fight for life but as soon as her resolve weakens and she pleads with the universe to end her misery, it's mere seconds before the pearly gates swing open and beckon her come hither.

Screenwriter Shauna Cross sidesteps a serious discussion of mortality by distilling the teenager's ruminations into a series of flashbacks and montages of an enviably carefree childhood and a fairy-tale school romance.

Add into the overwrought mix the heroine's natural aptitude for the cello and her impending audition for the world renowned Juilliard School for Performing Arts in New York City, and it seems churlish, not to mention ungrateful, for her to consider anything but a return to terra firma.

The musical prodigy is Mia Hall (Chloe Grace Moretz), who has never felt like she fits in with her parents Denny (Joshua Leonard) and Kat (Mireille Enos) or little brother Teddy (Jakob Davies).

"I've always felt like this Martian in my family," Mia tells Adam (Jamie Blackley), her school's resident dreamboat, who plays guitar in the band Willamette Stone and is destined for great things, including falling for Mia.

Their romance burns bright until Willamette Stone are signed to a record label and the pressure of touring takes Adam away from Mia.

Soon after, Denny and Kat pack the children into the car for an ill-fated drive down snow-laden roads.

Mia wakes from a head-on collision and watches paramedics rush her lifeless body into an ambulance.

At the hospital, where her grandparents (Stacy Keach, Gabrielle Rose) solemnly await news, Mia observes from a distance as medical staff attempt to save her life on the operating table.

"This kid's waking up an orphan... if she ever wakes up," one doctor tells his staff.

If I Stay shamelessly tugs heartstrings, constructing an idyllic cocoon of love for Mia, which is shattered to smithereens by cruel misfortune.

Moretz and Blackley are an attractive pairing and spark pleasing screen chemistry that sustains our interest through some mawkish and emotionally manipulative moments.

The fractured chronology is unavoidable but hampers dramatic momentum, reducing a middle section laden with reminiscence and regret to a crawl.

A hoary and contrived finale is sign-posted well in advance so teenagers have plenty of time to arm themselves with enough tissues to contain their sobs and sniffles.