Lest that title give the wrong impression, it should be said that writer-director Hong Khaou’s feature debut is unabashedly a dirge. Cheng Pei-pei plays a Chinese-Cambodian immigrant mourning the recent death of her son (Andrew Leung), and resenting him for having stashed her away in a London assisted living facility. Checking in on her there, by way of interpreter (Naomi Christie), is Ben Whishaw, playing the undeclared lover formerly known to this woman as her son’s “best friend.” Grief is the common ground neither of them ever wanted, a mutually unfamiliar territory, and among the losses lamented here are those of meaning in translation. Hong’s presentation seems cinematically straightforward, periodically muting conversations to focus on the unspoken, or setting an unembellished interplay of memories and fantasies against Stuart Earl’s funereal yet consolingly airy score. Muted delicacy prevails, and the movie comes across as a placid surface under which emotions sometimes may be seen to roil. Whishaw being an expert on such matters is good validation for Hong’s priorities, not to mention a lucky casting break. This film about language barriers and fragile incomplete relationships risks seeming itself untranslatable, fragile, and incomplete, but Cheng’s dignity and Whishaw’s sensitivity combine into something very much alive.