The “fourth wall” in theater describes the invisible barrier between the actors and the audience. In “The Boychick Affair — The Bar Mitzvah of Harry Boychick,” writer Amy Lord takes the fourth wall and drives a truck through it.

“The Boychick Affair” is the latest offering from Lord, who starred in the interactive play “Tony and Tina’s Wedding” before creating “Grandma Sylvia’s Funeral” in 1994. This time, Grandma Sylvia’s great-grandson Harry is becoming a bar mitzvah. After a successful two-year run in Los Angeles and a stint in Florida, Lord has brought her madcap creation to New York and everyone — well, almost everyone, according to the program — is invited.

Going to see “The Producers” is fun. Going to “The Boychick Affair” is an experience like no other on Broadway.

Maybe there’s something to all this talk about a resurgence of Yiddish. It seems that there are now two Yiddish theater companies in New York. A scrappy new outfit, the New Yiddish Rep, joins the National Yiddish Theatre—Folksbiene in bringing Yiddish entertainment to the masses. And while there were hardly masses at 45 E. 33rd St. for “The Big Bupkis,” the New Yiddish Rep’s newest production, there was a surprising amount of entertainment.

The star of “The Big Bupkis,” Shane Bertram Baker, may be the new incarnation of Yiddish theater — he’s relatively young, not Jewish, and learned his Yiddish as an adult. A child magician and a participant in the current burlesque revival (what, you didn’t know burlesque was reviving?) Baker is perfectly comfortable on stage and has great comic timing.

To celebrate its 95th consecutive season, the National Yiddish Theatre-Folksbiene is presenting “Sholom Aleichem: Laughter Through Tears,” a one-man commemoration of the 150th birthday of the beloved Yiddish humorist and writer. That one man — Theodore Bikel, a renowned actor and folksinger long associated with Sholom Aleichem through his portrayal of Tevye in “Fiddler on the Roof” — is 85 years old. Watching Bikel stride across the stage for almost two hours, speaking continuously, breaking his monologue only to launch into numerous songs, all these birthdays and milestones are much on the viewer’s mind. How could they not be? It’s an amazing accomplishment for anyone (How do actors remember all those lines?), but it would be dishonest (if a bit ageist) to deny that it’s even more amazing for someone his age. Bikel’s bulk and full white beard make for a commanding stage presence; the words flow easily and he never seems fatigued.

In Mark Altman’s play “Sin,” at the Baruch Performing Arts Center’s Rose Nagelberg Theatre, Satan, played by Grant James Varjas, describes himself as “the party not in power.” As the loyal opposition, he displays a Republican determination to bring things to a screeching halt. He’s furious at human beings for monopolizing God’s attention, and contemptuous of their piffling sins. Where are the real sinners like Cain, who wasn’t afraid to lie to God’s face, Satan demands.

Altman’s adaptation of Isaac Bashevis Singer’s short story “The Unseen,” directed by Kent Paul, puts the devil at the center of the action. Not only is Satan the most interesting character, but in many ways, he’s the most poignant.

There’s nothing more intimidating to a writer than a blank page, playwright Mark Altman ruefully explained to The Jewish Standard recently, so when he is ready to start a new theater project, looking at a printed story at least gives him a starting point.

“For many years, I’ve been adapting plays,” Altman said, starting when he was associate artistic director at the Folksbiene National Yiddish Theater. He began to read stories written by the classic Yiddish writers and turn them into dramatic pieces. Some of these went into a reading series.

“I pulled out a lot of these old chestnuts and tried to adapt them. I felt we had a chance to bring some pieces that couldn’t run for six or eight weeks, but were unusual or different,” Altman said.