Perverted doctors. A lecherous clergyman. Patriotic undies. Big boobs. Penises of all sizes. Such is the stuff of “Habeas Corpus.”

Directed by Cecilia Morelli ’04, the Dramat experimental theater production of Alan Bennett’s 1972 play has vulgar innuendo, trousers around the ankles, mistaken identity, and outrageous complications of all sorts — all the tried and true elements of British farce. In fact the production, running this weekend at the New Theater, has just about everything — except the vitality of farce.

A farce requires two things: it must be funny and its pacing must be tight. Always. And on these two points “Habeas Corpus” constantly flirts with danger as shamelessly as its characters flirt with each other. Bennett’s somewhat awkward plot coupled with moderate pacing dulls enough of the comedy to turn a rip-snorting romp into a humorous curiosity.

It takes about a half hour (of a two-hour production) before the pot starts to boil, before middle-aged Dr. Arthur Wicksteed (Zevon Odelberg ’04), his wife Muriel (Francesca Cecil ’04), and their son Dennis (Daniel Levin Becker ’06) all arrange to meet the objects of their desires on the same afternoon. Arthur and Dennis coincidentally plan to entertain the same coquette, Felicity Rumpers (Carolyn Rothman ’06), one of Arthur’s patients, while Muriel schemes to reconnect with an old flame, Sir Percy Shorter (Fran Kranz ’04). But instead of setting the rendezvous at the Wicksteed home, Bennett chooses three distinct locations for the encounters, thus avoiding a ticklish situation.

Bennett shies away from such confusion throughout his play, leaving his characters to slosh their own ways through the incestuous tale without the payoff scenes that beg to be staged. Both acts end with climactic tableaus, but the perfectly awkward situations, the untimely moments of convergence, and the webs of deceit — the heart of farce — are either conspicuously absent, stuffed in the play’s background story, or largely uninspired.

Yet every time the plot begins to slip, Morelli’s superior ensemble finds a way to pull the show back on track — or at least provide ample distraction.

And it’s easy to get lost in the details of each personality, starting with the irreverent, “Playboy”-reading Cockney maid, Mrs. Swabb (Amanda Eckerson ’06) who introduces the cast of characters in the prologue. There we meet the Wicksteeds, including Constance (Maeve Herbert ’04), Arthur’s socially inept sister who, with a flat chest, flared nostrils and saucer-sized glasses, remains hopelessly single as her youth slips away. That is, until she gets her mail-order boobs and meets a desperate Canon Throbbing (Peter Cook ’05), a tall, red-headed, red-blooded priest who believes that marriage will suppress his lustful tendencies.

Add to the mix Kranz’s stuffy and horny, self-important doctor with a dirty secret, Cecil’s enticing Mrs. Robinson-does-Britain, and Nick Tucci’s ’04 best impression of DeNiro in “Analyze This” (in a cameo role as a depressed suicidal), and “Habeas Corpus” is a veritable master class in character acting.

Kranz, Cecil and Herbert shine among stars, but Peter Cook is truly in his element and way over the top, especially as he stutters his way through a marriage proposal. Cook stands out in a cast that, oddly enough, shows considerable restraint, aiming for consistent smiles and chuckles without really playing for big uproars.

But characters do not make farce, and the actors have to fight more than just the script in this production. They have to battle a large stage of mostly undefined space (there are a couple flats, a pair of platforms, two chairs and a sofa; interiors dissolve into exteriors without warning) that drains any sense of the claustrophobia that ought to fill a sitting room when a pimple-faced boy announces he’s lost his virginity.

What is missing here is the zip. The audience has time to think between lines, between entrances and exits, between moments of chaos, and thought is fatal to farce. Still, what is left is an amusing, mindless sex comedy with outstanding performances and the insightful lesson that he whose lust lasts, lusts longest.