The reason that directors manage to co-exist with actors is that a show lasts a finite time and temperaments fugit. Take the case of Ed Sherin. In his last Broadway outing, he directed that most mercurial of stars, Nicol Williamson, whose credits include punching out producer David Merrick in 1965 and this season slapping a fellow actor at a curtain call of Sherin's Rex. Ed, who has a reputation as a so-called "actor's director," had no problems with Nicol. The one performer he seems inevitably to wrangle with is his most frequent female lead, Jane Alexander, who also happens to be his beloved wife. Williamson never laid a glove on Sherin, but Alexander is perfectly capable of flinging a script in his face.

"When we work together we treat each other as actor and director," Sherin explains. "The difficulty is that we take our disagreements home." "Sometimes it doesn't even get that far," Jane interrupts. "It starts in the car. When we were doing Major Barbara together, we kept fighting in the car until I stopped it and told him to walk home." That does not mean that Alexander is in the driver's seat. "You were damned good," Sherin recalls, "because you played it my way. You always come round to my way of thinking."

If Ed, 47, were a husband whose self-confidence is threatened by the acclaim for his 36-year-old wife, this would be the summer of his discontent. In the season after they finally married—after sharing eight years and a dozen plays as housemates—Jane starred in Eleanor and Franklin, TV's most successful obeisance to the Bicentennial to date (it outdrew Archie Bunker in his own time slot). Jane has another current splash in the blockbuster film All the President's Men, in which she plays the embittered, enervated CREEP bookkeeper who finally leaks to Dustin Hoffman. She shot the taut, difficult part during a pressured four-day break from a Noël Coward play. "We were all committed to that movie," she says. It is already being talked up for her second Oscar nomination.

Ed was, at the time, trying to save the troubled Rex, which, despite Williamson's starshells, closed in six weeks. "I don't think I'll ever direct another musical," sighs Sherin, who received only $6,500 for a year's work. He stood to make $150,000 if the show had a long run. "It was a gamble," he figures. "You can make a fortune that way, but not a living." Ed concedes that the competitive strains of showbiz can also make marriage a crapshoot. "I can feel our relationship is different now that I've come off a failure," he says. "But this works both ways. Sometimes I will be flourishing and Jane will be doing nothing."

In both The Heiress, which lasted briefly on Broadway this spring, and Eleanor and Franklin, Jane played the ugly duckling part that's making her practically the female Dustin Hoffman. "I grew up thinking I was never very pretty and so I was attracted to parts that weren't physically glamorous," she explains. "I could identify with them because they seemed to fit my own emotional past." She grew up Jane Quigley in Boston's Kennedy country, Brookline, where her Harvard-educated father, an orthopedic surgeon, encouraged her acting from the age of 6. Yet she majored in math at artsy Sarah Lawrence College, "so I could become an IBM programmer if things didn't work out." They did. She played in Tennessee Williams' Orpheus Descending at the Edinburgh Festival and returned to break into improvisational revues in New York.

Sherin was born to Polish Jewish immigrants who left Mississippi eventually for Manhattan. "My father was a textile worker and did not want me to go through the hardships he'd been through. But I rebelled, and at 16 I ran away." He drifted through the Southwest, working as a cowpoke and a busboy, before ending up a premed football player at Brown. During the Korean war he dropped out to join the Navy, "and I came out an actor. It was like being free."

He met Jane after he switched to directing and she auditioned for him at Washington's Arena Stage. "My impression was that he was attractive but arrogant," Jane recalls. He replies that he found her "a strong and powerful actress, but not nearly as strong as she is today." By then both of their earlier theatrical marriages—hers to director Robert Alexander, his to arts center manager Pamela Vevers—had closed out of town. They were soon living together and on their way to collaborating on a string of Broadway hits like The Great White Hope, 6 Rms Riv Vu and Find Your Way Home. Their retreat from show-business-as-usual is a peaceable kingdom in Putnam County, New York, about 45 miles from Broadway. There Jane runs an elegant, burgundy-painted clapboard farmhouse on an eight-acre estate including a trout stream. She is a passionate birdwatcher; Ed is a horticulturist extraordinaire. On weekends, the place overflows with their four children (one from Jane's first marriage, Jason, 11; three from Ed's: Tony, 16, Geoffrey, 12, and Jonathan, 10) who bunk in dormitory style. Drop-over friends include stage folk like Jane's The Great White Hope co-star James Earl Jones and old Sarah Lawrence chum Hope Cooke, the quondam queen of Sikkim. Laundry and dust accumulate between biweekly appearances by a maid.

Alexander's future includes more television "because that's where social problems can be dramatized. If I suddenly became a star, as opposed to an actress," Jane observes, "and Ed were never offered another job, the sheer fact that I was away all the time would be bound to damage us." Sherin responds: "Keeping a relationship going in this business without attendant jealousies is not easy." Lately, Ed and Jane were called to play together—on jury duty. "I'm still bewildered by it," says Alexander. "It's not odd at all," Ed insists. "Everybody knows we work better as a team."