Sunset might mark the end of your workday, but for some of the animals and employees at the Honolulu Zoo, it’s time to get busy.

The Honolulu Zoo Society is once again offering Twilight Tours, available from 5:30 to 7:30 p.m. Fridays and Saturdays, to provide a glimpse of what happens behind zoo gates when it starts to get dark.

The two-hour, guided walking tour allows visitors to watch as some of the animals prepare for bed while others are just waking up. Learn about animal biology and behavior and the zoo’s role in the conservation of endangered species.

“We’re excited to bring back weekend Twilight Tours to the Honolulu Zoo, which gives visitors a different experience and a chance to appreciate the work that happens around the clock to care for the animal residents,” said David Earles, executive director of the Honolulu Zoo Society, in a press release.

Comfortable walking shoes are recommended. Strollers and water bottles are welcome, but no outside food. Light refreshments will be provided after the tour.

Tickets are $20 for adults ($15 kamaaina), $15 for kids age 3 to 12 ($10 kamaaina), free for kids 2 and under. Tours can be booked at honoluluzoo.org.