Starring Blake Lively and Harrison Ford. Rated G.

In The Age of Adaline, Blake Lively plays a woman who stops aging, in 1937, at the age of 29. It’s the result of a car accident, a plunge into frigid water, and a lightning strike. But the movie seems less interested in the scientific possibility of her perma-youth than in the endless parade of era-specific gowns and sweaters the twist of fate allows.

We meet Adaline, under the assumed name of Jenny, in current-day San Francisco (a well-disguised Vancouver), working as a librarian who has an impeccably preserved wardrobe of vintage apparel at her disposal. She’s spent a lonely life hiding from authorities, as well as any friends or lovers she’ll inevitably outlive. But for most of this handsome-looking movie, the title character remains a glamorous but reserved clothes hanger. Lively tries to play Adaline with the sophistication of someone who is a century wise, but she does it with a cold remove that sucks too much of the emotion and pain out of this fantasy-romance.

Hers is a difficult role, but she’s aided by an unexpectedly strong cast. Ellen Burstyn, playing a daughter who passes herself off as Adaline’s granny, brings an affecting credibility to a child in the strange position of talking to her 20-something mother about retirement-home choices. Game of Thrones and Orphan Black beardie-hunk Michiel Huisman is soulful and passionate as the history buff who tries to woo her. And one of the film’s most pleasant surprises is Harrison Ford, who breaks his cranky-old-guy streak by generating real emotional depth and warmth as a man haunted by a lost love.

But they inhabit an exceedingly weird, albeit gorgeous, world. One of director Lee Toland Krieger’s stranger choices is the Twilight Zone–like narration by Hugh Ross, who frequently breaks the action to explain the implausible scientific hocus-pocus that drives events.

It’s an offbeat mix, indeed: schmaltzy romance, sci-fi-fantasy, and vintage-fashion show. And they might have pulled it off, too, if Adaline were just a little less… Perfect? Or is that the bitterness of someone who’s broken the 29 mark speaking?