Foul-mouthed puppets have been played for laughs before, but the Singapore Repertory Theatre's (SRT) staging of Hand To God is as much Exorcist as Avenue Q.

The American play runs from April 19 to May 6 at KC Arts Centre - Home of SRT. It features an anthropomorphic sock hell-bent on doing and saying things the confused puppeteer cannot.

Sex, a little violence and creepy scenes reminiscent of the Exorcist movie play out in the script written by Robert Askins.

The cast has already broken two tables and a chair during rehearsals, says actress Janice Koh, showing off her bruises.

She plays Margery, a recent widow who has roped her grieving teenage son Jason (Thomas Pang) into doing puppet shows at church.

Jason's sock puppet, Tyrone, turns out to have a vengeful, foul- mouthed personality of its own. Perhaps it is possessed or perhaps Jason is.

Pang, 27, says: "The question is not 'what is Tyrone', but 'why is Tyrone'? Tyrone is a coping mechanism for grief."

The cast includes Daniel Jenkins, Ann Lek and Gavin Yap. Puppet design is by Benjamin Ho.

The director is London-based Guy Unsworth, who is associate director to Christopher Luscomb and just came off a double-bill of Shakespearean comedies at the Theatre Royal Haymarket in the West End.

SRT's artistic director Gaurav Kripalani, 45, says he had access to the script when Hand To God was first staged in 2011, but did not think then that he would be allowed to present it here.

"It's a reflection of how much we have grown up that plays like this are being produced now," he says.

Last November, he starred in his troupe's staging of Disgraced, a Pulitzer Prize-winning play that confronted ingrained prejudice against Muslims in post 9/11 America.

Hand To God has been given an R18 rating for coarse language and religious references. No matter Tyrone's diatribes against organised religion, the cast and the director say that the play is not intended to hurt religious feelings.

It is about two people who have to reconcile their faith with a staggering personal loss.

Koh, 43, says: "Jason and Margery are forced to confront their demons and insecurities. It's very revealing about the state of their relationships and how they deal with their loss. And is it a loss of faith?"

Unsworth, 29, explains Tyrone's diatribes using a study where children who dressed up for Halloween behaved more mischievously than children in plain clothes.

"Once you're able to assume a different mask, you're inclined to be more naughty. That's what's going on here," he says.

Correction note: An earlier version of this story stated that Hand To God is rated M18. It is actually R18. We are sorry for the error.