New shows from Pig Iron and Quintessence make our "nice" list this week, along with holiday faves at the Walnut Street Theatre and Theatre Horizon. At Plays & Players, 1812 Productions revives its newsy "This Is The Week That Is" review. And the Forrest Theatre welcomes back those singing Mormons from the South Park guys.

"Gentlemen Volunteers"
(Pig Iron Theatre)
A revival of the popular story of two World War I ambulance drivers who travel from Yale to the battlefields of France. Preview Thursday, opens Friday (through Dec. 27).
Christ Church Neighborhood House, 20 N. American St., $20-$30, 215-425-1100.

"Hansel and Gretel" 
(Quintessence Theatre Group)
A contemporary retelling of the classic Grimm fairy tale. Previews Wednesday-Friday, opens Saturday (through Jan. 3). Sedgwick Theater, 7137 Germantown Ave., $15-$50, 215-987-4450.

"A Christmas Story"
(Walnut Street Theatre)
If you loved the 1983 film version, you'll love this musical. And if you hated the 1983 film version, you'll love this musical. Through Jan 20.
Walnut Street Theatre, 825 Walnut St., $20-$95, 215-574-3550.

"Black Nativity"
(Theatre Horizon)
This Afrocentric holiday tradition is a joyful, noisy alternative to all those grim Dickensians and cynical elves. Through Sunday.
Theatre Horizon, 401 DeKalb St., Norristown, $22-$49, 610-283-2230.

"This Is The Week That Is"
(1812 Productions)
Now marking its 10th anniversary, 1812's merry take on the highs and lows of current events is as fresh as ever. Through Dec. 31.
Plays & Players, 1714 Delancey St., $28-$42, 215-592-9560.

"Book of Mormon"
(Forrest Theatre)
The enthusiastic elders deliver their religious message in a winning and hilarious, but very much R-rated, song-and-dance package. Through Dec. 27.
Forrest Theatre, 1114 Walnut St. Through Sun., Dec. 27. Tickets: $67-$177, 800-447-7400.