DETENTION ★★½

(Comcast Movie Collections: Same Day as DVD) A multi-genre farce that’s all sugar and smirks and OMGs. It’s like someone beat a piñata until it rained texts and blogs, MTV and energy drink. The whole thing is set at a 2011 high school and conducts itself as high school movies do: in desperate need of attention. Yet if Joseph Kahn’s fevered music-video slasher farce is never intentionally bad, its unintentional badness keeps blasting into surprisingly clever places. (R; runs through Oct. 11)

ALAMAR ★★★

(Comcast Free Movies) A beautifully photographed, quasi-documentary from Mexico about a father’s visit to the Banco Chinchorro, the largest coral reef in the Caribbean, with his young son before the boy leaves to join his mother in Rome. Using real-life characters, naturalistic camerawork, and little dialogue, the film is a leisurely and lyrical journey through the timeless ritual of catching and cleaning fish, and the natural progression of paternal love. (Unrated; runs through Oct. 1)

JUST CAUSE ★★

(Encore on Comcast) Sean Connery (as a Harvard law prof turned detective in the Everglades) and Laurence Fishburne (as a surly, antagonistic homicide detective who may have framed Connery’s client) both do solid genre work. Credibility is undermined by a pileup of unconvincing action cliches at the end. (R; runs through Oct. 26)