WHEN YOU get down to it, the humor in "The Tall Guy" is pretty pedestrian, the kind of broad, eye-rolling British silliness even PBS wouldn't import. So why am I laughing more than I want to?

Mainly because of Yankee Jeff Goldblum. As the tall guy of the title, his gangly performance puts a much-needed, awkward oomph into an otherwise humdrum story. There are some forced comic "bits" he must do, such as sneeze convincingly (he can't), look fearful of injections (he can) and have cutely eccentric home habits, like eating cereal with water and sleeping in Superman pajamas (not cute, not eccentric, not funny).

But after getting over how weird Goldblum looks (it always takes me a few scenes), he breaks through. His strength is in improvising, bending a line, or throwing in an unexpected expression, a bewildered is-this-really-happening look. At one point, he's suffering quietly at a dinner date with a wacky, talkative woman he obviously wants to get rid of. "Screw wisdom," she says. "Who wants to be wise?"

"The Dalai Lama -- to name but one," says Goldblum with a nervous sputter.

Goldblum plays an American stage actor working in London who gets a job as the straight man in a successful West End show, opposite an unbearably hammy and ruthless comedian (played with sneery effectiveness by Roland Atkinson). He needs a personal life. He finds it when he goes in for allergy shots and falls for nurse Emma Thompson. From this point on, it's mostly boy-meets-loses-regains-girl plot inanity.

Speaking of inanity, a music-video-like sequence in which all the movie characters frolick about to the soft-rock song, "It Must Be Love," is at best, a questionable comedic ploy, as is the sign outside a quack doctor's door which reads "Dr. Freud."

But, to their credit, scriptwriter Richard Curtis and director Mel Smith mix in the dark with the dumb. "What a life," mutters Goldblum sympathetically, as a neighbor with dark glasses and a dog walks by, sneezing repeatedly. "Blind and allergic to his guide dog."

Goldblum, fired from his gig, is forced to take the main part in "Elephant!" an appropriately dreadful musical version of "The Elephant Man." Says a glib "Elephant" producer to Goldblum: "Well, they said 'Jesus Christ Superstar' was a stupid idea."

To which Goldblum replies, " 'Jesus Christ Superstar' was a stupid idea."

Actually, "The Tall Guy" was essentially a stupid idea. But, with Goldblum in it, and such "Elephant!" numbers as "Somewhere in Heaven, There's an Angel with Big Ears," the movie works in spite of itself.

THE TALL GUY (R) -- Area theaters.