The Knack. Comedy by Ann Jellicoe. Directed by Peter Gordon. The Roundabout Theatre Company has been whiling away the late-summer months with an across-the-decades British retrospective. First came ''Jeeves Takes Charge,'' at the Haft Theater, surveying the P.G. Wodehouse world of the 1920s and '30s - the world of Bertie Wooster and all those other chaps and blokes. Ann Jellicoe's ''The Knack,'' at Roundabout Stage One, moves the calendar forward to the swinging '60s, the Britain of Carnaby Street, Mary Quant fashions, and the Beatles.
And more particularly to the world of three young men sharing a nondescript London house. Schoolteacher Colin (Mark Arnott), the shyest of the trio, is also the landlord. As the lights go up on a large, almost bare basement room, tenant Tom (Daniel Gerroll), is giving his quarters an abstract paint job in black, white, and gray. Tom is the fantasist, the put-on artist, who keeps the world off balance with his glib word games. Tolen (John Abajian) is Mr. Macho, a muscular, self-proclaimed lady killer with a muscle-bound brain. Enter Nancy (J. Smith-Cameron), a wide-eyed, delicately featured brunette, who climbs through the window into the basement room and asks directions to the nearest YWCA.
Ranging from elliptical conversations to broadest knockabout farce, ''The Knack'' made me think of Harold Pinter with fun and games. Under Peter Gordon's direction, the cast of the Roundabout revival acts out Miss Jellicoe's ultimately pointed charade with the blend of light touch and earnest attitude essential to the art of comic playing. Mr. Gerroll delivers Tom's deadpan routines with masterful aplomb, while Mr. Abajian sees both the silliness and insecurity of Tolen's sexist braggadocio. Mr. Arnott's Colin is an appealingly earnest, diffident, and frustrated naif - a latter-day version of the worm who turns. As for the delectable actress with the formidably double-barreled name of Smith-Cameron, she is a piquant Nancy whom any right-minded young hero would fancy. In fact, Miss Smith-Cameron is a love.
The production has been attractively designed by Douglas Stein (set), Ronald Wallace (lighting), and Jane Clark (costumes).