Sex sells, they say, but in David Hare's tedious "The Blue Room," it qualifies as something less than a bargain.

Sitting through the play at Signature Theatre, you find yourself dividing your attention between the ministrations of the two actors onstage and the staccato progress of the second hand on the dial of your watch. It's difficult to make the case that either activity is any more captivating than the other.

The intermissionless piece takes an audience through 10 vignettes of seduction and lovemaking, each one suggesting, surprise, surprise, that we are all capable of caddish behavior, that the face we put on for one lover is different from the one we might put on for the next. The idea is driven home not once, not twice, but 10 mechanical times. "Do you think we're ever just one person?" a character asks late in the play, on the off chance that we've drifted into sleepy-bye during vignettes three through seven and failed to absorb the inescapable lesson of the evening.

"The Blue Room" is modeled on Arthur Schnitzler's "La Ronde," a play that scandalized turn-of-the-20th-century Vienna with its depiction of sexual affairs. The gimmick of both "La Ronde" and "The Blue Room" is in the linking of the 10 scenes: One of the partners from each tryst goes on to a second dalliance in the next sequence. In "The Blue Room," a cabby who hooks up with a prostitute turns up in the following scene with an au pair; the au pair then has an affair with a law student, who in the next scene falls into bed with a married woman, and so on.

One actor (Rick Holmes) and actress (Deborah Hazlett) play all of the lovers, which means they dress and undress a lot in front of us. (Too bad no one thought to seek out Victoria's Secret as an, um, underwriter.) A sophomoric instructional aid is also supplied: During the blackouts that indicate a sex act is taking place, a projection tells the audience in scorecard fashion how long, in minutes, each of the assignations takes.

Still, for all the bed-hopping, "The Blue Room" radiates about as much eroticism as "Shrek 2." From Michael Brown's abstract set shaped like a curlicue, to Wendy C. Goldberg's sparkless direction, it's all pretty sterile stuff. Affecting convincing British accents, Holmes and Hazlett try and try to give some bite to Hare's antiseptic creatures, but they're required all evening to embody toothless stereotypes: the randy politician, the wayward adolescent, the narcissistic playwright. Some of the sex scenes play as farce, though not nearly at the level of experts like Ferenc Molnar. They are more like rehashes from that silly old TV series "Love, American Style."

Hare's play was a bit of a sensation in London and later, New York; the cause of most of the hoopla was the casting of Nicole Kidman and, more to the point, her willingness to bare a little flesh. (Her peep show was ever so tasteful and brief.) Hiring an actress on her way to global stardom, however, is what it apparently takes to make a success of "The Blue Room."

The Signature management notes that "The Blue Room" may not be suitable for younger audiences. The warning could use some broadening. It's no picnic for adults, either.

The Blue Room, by David Hare. Directed by Wendy C. Goldberg. Set and lighting, Michael Brown; costumes, Anne Kennedy; sound, Timothy M. Thompson. Approximately 1 hour 35 minutes. Through July 11 at Signature Theatre, 3806 S. Four Mile Run Dr., Arlington. Call 703-218-6500 or visit www.signature-theatre.org.