BOTTOM LINE: A witty yet impactful look at two New York couples and the difference a baby can make.

Babies: they’re little, they’re cute, and they compromise otherwise healthy adult relationships. They also can define a family. In Daniel Goldfarb’s polished dramedy, Cradle and All, one little screaming bundle represents the conflict at hand for two Brooklyn couples.

Claire and Luke seemingly have it all in their schmancy Brooklyn Heights digs. They are good looking, well dressed, and professionally successful (more or less). In their mid to late 30s and together five years, they are unmarried and don’t appear to have plans of settling down into a traditional domestic situation. This would be fine, except that Claire desperately wants a baby. Across the hall, Annie and Nate negotiate parenthood, as the proud and burned out parents of an 11-month old. Their life has taken a drastic turn to poopy diapers and plastic teething toys, although music posters on the walls echo of their past, hipper life. Annie and Nate’s disheveled existence is the antithesis to Claire and Luke. The couples are well acquainted with each other, and throughout Cradle and All, grass-is-always-greener references are made to a very different lifestyle.

Although Cradle and All incorporates four characters, it only uses two actors — Maria Dizzia and Greg Keller — who each play two roles. Act I reveals an awkward evening between Claire and Luke in their apartment, and Act II takes place across the hall with Annie and Nate as they struggle to sleep train their screaming baby. This narrative device works exceptionally well because even though the couples seem to live opposite lives, the tensions can, in fact, be very similar. Each decision — to marry and have kids, or to focus on your career and independence — comes with its own relevant issues.

Dizzia and Keller are tremendous in their roles, which adds to the delight of double casting. During intermission, as the set morphs into the neighbors’ apartment, Dizzia and Keller undergo their own transformation, emerging stripped of Claire and Luke’s fashionable, groomed, power-demeanor. In Act II, their sweatpants and messy hair project utter exhaustion. The difference is so drastic (visually as well as within the actors’ character work) that during the curtain call, I fully expected Claire and Luke to come out and bow.

Goldfarb’s sincere script and Sam Buntrock’s playful direction allude to the comfort that gets built within long-term relationships; when awkward conversations occur and partners don’t see eye to eye, this comfort can be deeply shaken. This is what occurs between both couples in Cradle and All. When a resolution seems questionable, the result is heartbreaking. Dizzia and Keller are perfectly cast as conflicted better halves; they communicate a vulnerability that seems all too relatable.

MTC’s production values shine through this production, with a gorgeous set by Neil Patel that transforms into two contemporary apartments with very different inhabitants (and also allows for cookies to be baked from scratch). Mattie Ullrich’s costumes are wholly appropriate, with Claire and Luke looking stunning and Annie and Nate looking, well, like the parents of an 11-month old. Light and sound design, by Ken Billington and Jill BC DuBoff respectively, further unify the professional production.

Cradle and All might give equal stage time to two different lifestyles, but it makes some unconscious statements about which is preferred. One act ends optimistically, the other not so much. Although these characters encounter turbulant times, the importance of family rings true. The Act II team presumably wins the happiness game, at least for now.

(Cradle and All plays at Manhattan Theatre Club’s NY City Center Stage, 151 West 55th Street, through June 19, 2011.  Performances are Tuesdays at 7PM, Wednesdays at 2PM and 8PM, Thursdays and Fridays at 8PM, Saturdays at 2PM and 8PM, and Sundays at 2PM. Tickets are $80. Student tickets are available for $25 at the box office beginning at noon, day of performance.  For tickets and more information, visit manhattantheatreclub.com.)

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