"A Hero Ain't Nothing but a Sandwich," never moves beyond its catchy title to explore the real pain, anxiety and questioning that must exhaust a family faced with a youngster's drug addiction.

As a result, "Sandwich," now playing at several area theaters, becomes a prime social statement film fo the restless high school assembly but not the riveting exploration of contemporary life its outline suggests for the mass audience. It is superficial and predictable but, worse, detached - and detachment from a monumental social problem like drugs is a disgrace.

Participating in the unwieldy "Sandwich" is a fine roster of talent. The cast is led by Larry Scott, the addicted teenager. His mother is played Cicely Tyson, his grandmother by Helen Martin, and his mother's boyfriend by Paul Winfield. Glynn Turman and David Groh portray the high school teachers.

Behind the cameras were: Robert B. Radnitz, The producer who is current Czar of familp films; RalphNelson, the director "Lilies of the Field" Cinematographer Frank Stanley ("Magnum Force" and "Car Wash") Photographer Larry Sxhiller (the creator of the montages in "Dutch Cassidy and the Sundance Kid'). Alice Childress, and awaCassidy and the Sundance Kid"). Alice Childress, and awaook fo the screenplay, and Tom McIntosh enlisted for the score. But all these good intentions, and fine skills, suffer from a sevee case of the blahs.

The hero, Benjie Johnson, an attentive, questioning youngster, has rejected the positive role models in his Los Angeles neighborhood of Watts and the affection of his mother's live - in boyfriend. He starts his drug odyssey by stopping on a rooftoop and smoking marijuana and drinking wine.

A friend introduces him to a stronger afternoon delight - heroin Scott starts stealing and delivering drugs for the pusher, played Kevin Hooks. When he falls asleep in class and ends up in a detozification center, the fanily and the movie start moving.

When Scott breaks through the timid perimeters of his role, his interpretation of a youth grabbing at maturity vibrates.

But only once do the emotions really flow - when Tyson, frustrated that her son hasn't been cured, plunges him into a bath of blue indigo, Then she jumps fully clothed into the tub with him and tries to explain her turmoil. But, by that time, It's too late for "Sandwich" to be saved.