Baltasar Kormakur’s “The Sea,” an Iceland-based tale of a highly dysfunctional family, may be thought of as “King Lear” with a Scandinavian accent. Thordur (Gunnar Eyjolfsson), the aging owner of a fishery that’s the dominant economic force in a coastal village, has put day-to-day control of the business in the hands of his nebbishy older son Haraldur (Sigurdur Skulason), a milquetoast with an alcoholic wife named Aslaug (Elva Osk Olafsdottir) and three self-absorbed kids, but the old man is anxious to make new arrangements. He summons home his two other children: Agust (Hilmir Snaer Gudnason), a handsome fellow who he believes has been studying business but has instead turned to writing, and who brings along his musician girlfriend Françoise (Helene de Fougerolles); and embittered daughter Ragnheidur (Gudrun S. Gisladottir), a frustrated would-be filmmaker married to hapless Morten (Sven Nordin) and with a surly teenaged son. They’re welcomed–if that’s the word–not only by their father but by his ultra-reserved wife Kristin (Kristbjorg Kjeld), the sister of the siblings’ late mother, and her reckless daughter Maria (Nina Dogg Filippusdottir), who’s obviously smitten with Agust and envious of Françoise. Watching over all the fireworks that result is the cynical, sharp-tongued, hard-drinking grandmother Kata (Herdis Thorvaldsdottir).

The first half of “The Sea” has a good deal to offer. The clan’s antagonisms are laid out with a healthy dose of dark humor, and the juxtaposition of the village’s stifling small-town ambiance with the younger generation’s modern attitudes is quirkily amusing; the result is almost like an Ingmar Bergman movie with laughs. Even the impenetrable commotion over fishing quotas sounds intriguing. While the family quarrels simmer at relatively low heat, moreover, they retain a certain fascination. Around mid-point, however, the tone shifts to one of high-strung melodrama. People shriek at one another and engage in acts of violence and destruction. The picture becomes increasingly hysterical–which might be fine if it were still intended to be funny. But that doesn’t seem to be the case. Taken straight, the second half of picture grows more and more ludicrous, like some compendium episode of “Dallas” or “Dynasty,” but with snow. By the time it ends, everyone has been ravaged, family secrets have been revealed and family heirlooms smashed, and retirement in Reykjavik beckons.

The switch in tone doesn’t aid the cast, who come off far better in the more sedate initial sections than the rambunctious later ones. Eyjolfsson bellows like a growling patriarch should, and Kjeld is an appropriately subdued doormat for him; Thorvaldsdottir spews out the humorous venom very effectively as grandma. Among the younger players, the blandly handsome Gudnason is effectively conflicted (until called upon to go berserk in the last reel), and De Fougerolles classily beautiful; but both Gisladottir and Osk Olafsdottir chew the scenery overmuch, as does Dogg Filippusdottir as the sensuous cousin. The secondary figures–a bank official, a dim-bulb local cop–are quirkily intriguing, and the atmosphere of a remote town where rams still wander onto main street from the wilderness (but oddities loom beneath the surface) is nicely caught–the result, especially in the early reels, is often not unlike a chillier version of “Northern Exposure.”

But while tragicomedy can be a powerful form, in this case the two elements haven’t been successfully merged; one just subsumes the other. In attempting too much and accomplishing too little, “The Sea” ultimately gets dramatically waterlogged.