For an hour one recent evening, Ms Melissa Zheng found herself trapped in a darkened room with three friends, surrounded by eerie music, strange paintings and a series of jumbled numbers and letters.
To get out, the 22-year-old economics graduate had to solve an array of mind-boggling puzzles that required a combination of wits, powers of reasoning and an observant eye.
No, she was not filming the next instalment of Saw. Neither had she been kidnapped by a mad scientist.
In fact, she and her friends had happily paid $22 each to be locked up at Xcape Singapore, a company in Purvis Street that features "puzzle rooms".
Even though they did not manage to get out of the room before the one-hour time limit, she says: "It was quite exciting and things got a little scary towards the end."
Xcape is one of three companies here that host puzzle rooms. All were set up this year and another is slated to open officially later this month.
They charge $15 to $37.50 for one attempt to solve puzzles in a room and this usually lasts an hour. Some sell drinks on the premises, although these are not allowed to be taken into the puzzle rooms.
All the rooms are equipped with a telephone or button so that participants can seek help if need be.
They usually have about an hour to come up with solutions to a series of challenges, with the ultimate goal of escaping the room. Some of the challenges are physical, such as retrieving a key from a hard-to-reach place in the room, while others involve arithmetic brain teasers or breaking codes.