On Demand movie highlights

A Love Song for Bobby Long ½

(Showtime on Comcast) John Travolta, with silver hair meant to suggest old age (it doesn’t), is the alcoholic disgraced professor of the title, living out his days in New Orleans with only a young novelist (Gabriel Macht) for company until Scarlett Johansson shows up as the daughter of one of his ex-loves. Travolta provides some fine Southern-baked ham, but this is the kind of movie that gives quirkiness a bad name. (R; runs through April 29)

Ty Burr

Men in Black 3 ½

(Starz on Comcast) About as good as one could hope for from an unnecessary sequel that’s a decade late to the party. Alien-containment agent J (Will Smith) time-travels to 1969 to rescue partner K. For all the millions of dollars spent on digital astonishments, the most uncanny special effect is Josh Brolin as the young Tommy Lee Jones. (PG-13; runs through April 30)

Ty Burr

Full Metal Jacket

(Encore on Comcast) Stanley Kubrick’s Vietnam film, five years in the making, is at its best in its Marine boot camp scenes. In a cold, psychotic way, they emphasize the dehumanizing of recruits turned into robotic killing machines. But the film falters when it moves to Vietnam. There, its detachment costs it force and focus. (R; runs through April 30)