AFTER a brief but ecstatic 40th-anniversary outing last fall, “Hair” will return to Central Park this summer as one-half of this year’s Shakespeare in the Park.

“Hamlet,” starring Michael Stuhlbarg (“The Pillowman”), kicks off the season of free, al fresco performances on May 27. It’s the first “Hamlet” since 1975, when Sam Waterston had the title role.

A concert version of “Hair” played just three nights in September. It will return in a fully staged production from July 22 to Aug. 17, again with Jonathan Groff – the brainy rebel of Broadway’s “Spring Awakening” – as the Vietnam-bound Claude.

For information, call (212) 539-8750 or visit publictheater.org.