The music comes up: Tchaikovsky. The lights come up: Richard Nixon. Even though he has his back to us staring out the window of the Lincoln Sitting Room, the hunched shoulders and the thrust of the head are unmistakable. He is incarnated for us courtesy of actor Edward Gero in "Nixon's Nixon," the Round House production of which is more pure, perverse pleasure than anything that's been on Washington stages for years, an energetic, live-action political cartoon with surprising undertones of sympathy and sadness. It and Gero's performance are explosive enough to drive Oliver Stone's movie "Nixon" out of your mind.

Playwright Russell Lees has imagined a meeting between Nixon and Henry Kissinger (Conrad Feininger at his most arrogant, Teutonic and amusing) on Aug. 7, 1974, roughly a day and a half before Nixon resigned. The two political masters are set on a collision course, as Nixon tries desperately to figure out a way to hold on to power while Kissinger tries to save his own career by persuading Nixon to resign. They joust like the wily, ruthless old pros they are -- and like the friends they almost were -- with first one and then the other gaining the upper hand.

Lees is a deadpan absurdist with a witty, off-center sense of dialogue. In a flashback discussing the secret decision to bomb Cambodia, Nixon points out a catch: "What about Sihanouk? He could screw us. We're bombing his country. He's bound to find out." Later, plotting with Kissinger to make the North Vietnamese think he's a crazy guy who might do anything, he muses, "We can't just send Ho Chi Minh a letter saying `Nixon's a banana!' He'll have to figure that out for himself."

Hunching around the stage, dark eyes darting and shadowed jowls a-quiver, Gero is simultaneously caricature and suffering human being. Gero has often been excellent onstage, but he's never before been this sheerly delicious. The performance is so audacious, and so much fun, that it's almost giddying: You gape as much as you laugh. Gero is partnered brilliantly with Feininger who, with his rigid back and cool, bespectacled gaze, makes Kissinger a menacing cartoon of ambition.

William Foeller's direction is vibrant, subtle and smart. Even in the early, hilarious part of the play, he's preparing us for its final poignancy. He guides Gero from a rousing, over-the-top beginning to a crumpled, bottomed-out end. "The strain," Gero mutters, collapsed against a footstool, "it's . . . unbearable," and he hits the last word with a flat finality that shocks us into compassion for this despicable man.

Elizabeth Jenkins McFadden's set, where the characters pace and sit and drink, is almost homey, though backed by a crumbling Great Seal of the Presidency. There isn't much sound -- some classical music, some very appropriate '60s songs, the skittering roar of a helicopter -- but Neil McFadden has designed it beautifully, and Martha Mountain's lighting is as inventive and witty as the script.

Lees has a gift for the telling turn of phrase, as when Nixon describes John Kennedy after the 1960 election: "He's sitting there all rich and presidential -- like a cut of veal." And he can combine what would seem to be mutually exclusive qualities, like somberness and humor. Discussing suicide, Nixon explains, "That's the catch. You never know when it's time to kill yourself until it's too late. Then, by the time you've figured it out, the moment is gone."

If the play were just another dump-on-Nixon exercise it would go sour quickly. Instead, it turns into a meditation on loss and blasted dreams, a little lesson on the mortality of hope. This is Lees's only play -- his previous creative work is as a designer of computer games based on Edgar Allan Poe stories -- and it's a weird little winner.

Nixon's Nixon, by Russell Lees. Directed by William Foeller. Assistant director, T.J. Keiter; costumes, Rosemary Pardee. At the Round House Theatre through April 25. Call 301-933-1644.

CAPTION: Nixon (Edward Gero) and Kissinger (Conrad Feininger) matching wits and wiles in "Nixon's Nixon."

CAPTION: Edward Gero is a tormented Richard Nixon, and Conrad Feininger an arrogant Henry Kissinger, in "Nixon's Nixon."