(L to R): Eldest brother Netanel (Roy Assaf), middle child Dorona (Rotem Zisman-Cohen) and youngest sibling Shai (Asaf Ben-Shimon) search for their biological father in the comedy-drama “The Kind Words.” (Strand Releasing)

The Israeli comedy-drama “The Kind Words” opens with the whirr of a projector, showing what appear to be home movies of a romantic encounter. Suddenly, the film breaks and burns through. The impressionistic start is at odds with the more ordinary style of storytelling writer-director Shemi Zahrin uses throughout the rest of the film, about three Jewish siblings struggling with their mother’s secret past. Still, it’s an apt metaphor for the memories that are broken by the film’s revelations.

When Yona (Levana Finkelstein) is diagnosed with a tumor, her three grown children come together for support. But the hospital waiting room turns into a complicated family affair when their father (Sasson Gabai) shows up with his second wife, a young actress. When Yona suddenly dies on the operating table, Dad reveals something that changes what everyone thought they knew about him: The man has never been able to have children. This news sets in motion the siblings’ search for the Algerian Muslim with whom their mother had a lifelong affair.

The three siblings are very different: Temperamental middle child Dorona (Rotem Zissman-Cohen) is separated from her husband Ricky (Tsahi Halevi), who remains hopeful that they can reconcile. The elder brother Netanel (Roy Assaf) is the most traditional member of the family, while the younger, Shai (Assaf Ben-Shimon), is bisexual. Like all families, the dynamics of communication — or the lack thereof — make their common goal all the more difficult.

At times, the film seems pat in its portrayal of modern Judaism struggling to maintain tradition in a changing world. Tonal shifts are problematic, with a maudlin score that evokes television melodrama giving way to quirky, sped-up sequences that treat family drama as light hijinks (although they’re meant to convey urgency, as the siblings get closer to the truth). Comedy turns surreal when the siblings’ quest leads them to a cafe that pays homage to singer Izhar Cohen, who in 1978 became the first Israeli winner of the Eurovision Song Contest.

That Eurovision winner proves key to deciphering a kind of baby talk that Yona once used with her daughter. As a plot point, it’s a nod to the power of pop culture to bring people together. Yet the film itself doesn’t always come together.

The final act is a departure from a narrative that is, for the most part, conventional. Although the siblings eventually learn the truth, there’s no real closure. Life is a mess, the film suggests, that we may never understand.

The title’s kind words, spoken by Ricky to his wife, are “I love you.” But as the film only intermittently demonstrates, those words are far from easy to say, whether by family or by lovers.

Unrated. At the Avalon.
Contains nudity and sexual situations. In Hebrew with subtitles. 118 minutes.