Thirteen years after Singaporean actress Lydia Look took to the stage on home turf in Action Theatre's Pillow Talk, she returns next week for Checkpoint Theatre's latest offering, The Way We Go.

She is taking the lead role of Agatha Mao, a former principal of the fictional Convent of Our Lady of Lourdes.

The 90-minute play, written by Joel Tan and directed by Checkpoint's joint artistic director Claire Wong, looks at the lives of Agatha, her best friend Violet (played by Neo Swee Lin) and her love interest Edmund (Patrick Teoh), focusing on themes of romantic and platonic love among those who are getting on in their years.

The themes of growing up and growing old are also paralleled by the younger characters played by Julie Wee and Chng Xin Xuan, who are convent students taught by Agatha.

The convent school setting is a familiar one for Los Angeles-based Look. "When I read the material, the connection I had with it was instantaneous. I grew up in convent school for seven years, so I'm very much a product of that era," says the actress, who is in her 30s and has had roles in Hollywood series such as Pushing Daisies (2007-2009) and NCIS: Los Angeles (2009-still showing).

"We had a very strict academic routine. Just imagine the musical The Sound Of Music - it was like that. We were always singing songs.

"It's challenging for me to play Agatha. I feel responsible to get it right because convent school kids will come and watch this."

While visiting her ageing mother in Singapore, she auditioned and got the part of Agatha, and is now based here for the next few months.

Look says she modelled Agatha after two of her primary school teachers at CHIJ Katong Convent, Ms Rosalind Tok and Mrs Coreen Isaac. "They were great friends. They are the real-life Agatha and Violet," she says, adding that she mish-mashed her mentors in shaping the role of Agatha.

Another "convent school kid" is Neo who, like co-star Look, attended CHIJ Katong Convent. The 51-year-old theatre veteran says: "I'm a convent girl born and bred. It resonated very much with me."

Her character Violet marries late in life at 56 and urges her best friend to fall in love and not waste time. Incidentally, it is her cousin, Edmund, that she nudges in Agatha's direction.

Playwright Tan, 27, says he was moved to write the script in 2011 after a conversation he had with a friend from a convent school.

"We had these old-time school teachers - you know, in their 50s and 60s, single. I was always curious about that - what if they met love late in life, would the added years lend their relationships an added maturity?" recalls Tan, who attended Montfort Secondary School, an all-boys Catholic mission school.

The play was originally written for his playwrighting course at the National University of Singapore, then taught by Wong's husband Huzir Sulaiman, Checkpoint Theatre's other artistic director.

Tan is now Checkpoint's associate artist. This is his first full-length play for the company and Wong first heard it three years ago during a "marathon" reading held at her and Huzir's house, a quirky tradition for the students of his course.

She says: "The characters leapt out at me. They are of such different ages and the love relationships in the play are not the usual ones you hear about."

Though four of the five characters in the play are teachers, the play is not really about the profession.

"It's more about the profound idea of teaching - the kind that doesn't happen in the classroom," explains Wong, 50.

And though there are elements of illness and death in the play, it is not all doom and gloom. Tan says: "It's painfully funny and also very melancholic and sad at the same time. It's like life. It's about the paths we take. It's just the way we go."