Demand for tickets to the much-anticipated superhero movie Avengers: Endgame has crashed cinema operators' websites here.
Long queues have also been spotted at popular cinemas such as Shaw Lido.
Meanwhile, sellers have appeared on online marketplaces like Carousell, offering tickets for sought-after time slots at many times their original price.
Tickets for the movie, which opens on April 24, went on sale yesterday morning.
The issue seems to have affected the online platforms of the major chains, including Golden Village, Shaw Theatres, Cathay Cineplexes, and Filmgarde Cineplexes.
A check by The Straits Times at 1pm yesterday showed that while it was possible to use the Golden Village (GV) app to log in and select seats, attempts to complete the booking would cause the app to freeze. The Cathay and Filmgarde websites appeared unresponsive, even on the homepage.
A GV spokesman said: "With the overwhelming demand for tickets to Avengers: Endgame, our website experienced extremely high traffic and customers had to wait longer than usual to purchase their tickets."
On the Shaw website, those buying tickets said they received a queue number.
A spokesman for Shaw said: "Shaw Theatres has activated our queue system for public access to our website and for online bookings for all movie titles, including Avengers: Endgame.
"This is to help us better manage the extraordinarily high volume of traffic to our website at the moment. This is a temporary situation and we expect it to be resolved relatively soon. Ticketing is as per normal at the box office at all our cinemas."
Avengers fan Karen Lai, 43, had been trying to use the websites of major cinema chains to purchase sought-after April 24 evening-slot tickets, but had either been put in a queue or seen her browser freeze when completing the transaction.
"I hate spoilers, so I want to watch it on opening day, after work," said Ms Lai, a vice-president for communications.
On Carousell, a user named "ulath" was trying to sell two tickets at $888. They are for the 2.50pm slot at Cathay Cineplex Jem on April 27, a Saturday. Users have responded to the seller with jokes and teasing.
"Hmm I could watch a movie, or for that amount buy a ticket to fly to South Korea," said one user.
On a brighter note, GV said it sold over 15,000 tickets in the first hour, surpassing all previous advance ticket sales records for a single movie. It added that tickets across its four Golden Village Gold Class cinemas were close to selling out for the first week of the movie's release.
A spokesman said: "Golden Village experienced unprecedented demand for tickets online and customers even queued for tickets across all 13 multiplexes before the cinemas opened."
Avengers: Endgame is expected to break box-office records worldwide and in Singapore.
In the United States, early demand for tickets also crashed websites last week. AMC Entertainment Holdings, the biggest American theatre chain, could not handle the traffic when tickets first went on sale. Fandango, a top ticket supplier, also struggled to meet demand and had to put customers in lengthy queues.
Even with the glitches, the film broke Fandango's first-day US sales record, topping Star Wars: The Force Awakens from 2015.
- Additional reporting by Desiree Loh