Tina Packer, right, and Elizabeth Aspenlieder will play mother and daughter in ‘The Beauty Queen of Leenane,’ a dark Irish comedy at
Tina Packer, right, and Elizabeth Aspenlieder will play mother and daughter in ‘The Beauty Queen of Leenane,’ a dark Irish comedy at Shakespeare & Company in Lenox in August. (Courtesy of Shakespeare & Company)

If I've learned anything over the centuries I've been writing about theater, it is that you should expect the unexpected. What often looks promising on paper can come a cropper on stage, and what falls beneath your radar can turn out to be a gem.

On the whole, this summer looks to be one of the most diverse and stimulating in recent memory.

So, with two productions -- "Bashir Lazhar" at Barrington Stage Company's St. Germain Stage and "Master Class" at Shakespeare & Company's Elayne P. Bernstein Stage -- already up and running, here's what's catching my attention as the Berkshires summer theater season gets under way.

1. Williamstown Theatre Festival's season

What has struck me most about Jenny Gersten's tenure as WTF's artistic director is her fearless creativity; her keen sense of honoring the late Nikos Psacharopoulos' vision of the festival in looking to the future by creating a sanctuary for theater artists -- directors, actors, writers, designers -- to ply their craft and art.

This summer, Gersten's third at the helm, is a perfect example, with two musicals on the Main Stage -- one old, "Animal Crackers"; one brand new, "The Bridges of Madison County" -- and the return of WTF veteran Nicholas Martin. Gersten's immediate predecessor as WTF artistic director, to direct George Bernard Shaw's "Pygmalion," while in the Nikos Stage, Gersten has a world premiere musical about the curse of the Bambino, "Johnny Baseball"; a world premiere comedy," American Hero"; a guest production by the innovative Brooklyn-based Debate Society called "Blood Play"; and the return of another WTF veteran, actress Kate Burton in "Hapgood," by one of my favorite playwrights, Tom Stoppard.

2. Chester Theatre Company's season

After hitting an all-time high with its extraordinary 2011 season, CTC went seriously off-track last summer. This summer, however, holds huge promise, beginning June 26-July 7 with a world premiere, "Arms on Fire," a play by Steven Sater with music by Duncan Sheik, the two creators of "Spring Awakening," and ending Aug. 15-25 with the regional premiere of an unusual take on Homer's "The Iliad," titled "An Iliad." And there's the regional premiere of "Body Awareness," a comedy by Amherst native Annie Baker. But what draws my attention most this summer at CTC is "Tryst," July 11-21, a haunting two-character play, set in Edwardian England, about a thoroughly amoral bounder who bleeds spinsters dry of their savings, and his latest victim, a milliner, who moves this cad's career in a stunning direction.

Elsewhere:

n Martin McDonagh's "The Beauty Queen of Leenane" is a tough, gritty, no-holds-barred drama about the nightmarish relationship between a demanding, manipulative mother from hell and a sacrificing but no-less-tough spinster daughter who gives as good as she gets. With Tina Packer and Elizabeth Aspenlieder as the combatants, this production at Shakespeare & Company's Elayne P. Bernstein Theater (Aug. 8-Sept. 15) looms as the summer's hot-ticket event.

n Bernard Slade's "Same Time, Next Year" (July 23-Aug. 10) is a sweet, harmless comedy confection. What gives this production at Berkshire Theatre Group's Fitzpatrick Main Stage so much appeal is the casting of Corinna May and David Adkins as the once-a-year lovers.

n Talk about couples: How about Treat Williams and Jayne Atkinson as King Henry II and his queen, Eleanor of Aquitaine, in a battle royal over the succession to the throne in James Goldman's "The Lion in Winter" at BTG's Fitzpatrick Main Stage, June 25-July 13.

n Stageworks/Hudson's annual season-opening collection of original one-act plays, "Play By Play," has always been one of my favorite theater evenings.

This year's anthology, "Unchained," features 10 short plays about life's constraints and how we break them or don't. "Play By Play" opens the season, June 12-23, and the American premiere of "Stockholm," an erotic thriller by Bryony Lavery, Aug. 14-Sept. 1, closes it. Laura Margolis, Stageworks' fearless artistic director, has a knack for finding particularly stimulating, provocative plays. Last season's "Tomorrow in the Battle" was a prime example. This play about a sexually charged couple holds as much promise.

Also on the radar:

-- "On the Town," Barrington Stage, June 12-July 13.

-- "Oklahoma!" BTG, July 1-20.

-- "Mother Courage," Shakespeare & Company, July 26-Aug. 25.

-- "The Fox on the Fairway," Oldcastle Theatre Company, Aug. 9-25.

-- "Scott and Hem in the Garden of Allah," Barrington Stage, Aug. 15-29.

-- "Young Frankenstein," The Theater Barn, Aug. 22-Sept. 1.

See you on the aisle!