BalletX succeeded in the last 18 months of the COVID-19 pandemic while more than most dance companies struggled. It kept its dancers employed and was one of the first to develop a digital program, with a series of immersive dance films. It performed at a number of prestigious dance festivals, and in June made its premiere at the Mann.

Thursday night, the company returned to the Avenue of the Arts for the first time in two years, with its premiere at the Suzanne Roberts Theater, performing its now classic and achingly beautiful Sunset, o639 Hours.

It was wonderful, confusing, weird, emotional. I printed out my tickets, grabbed my required mask and proof of vaccination, and headed to the theater, which was 70% full but still felt like a lot of togetherness.

Sunset, created by Matthew Neenan (who founded BalletX with Christine Cox and is an in-demand dance maker) and New Zealander Rosie Langabeer (who composed the score), is in many ways BalletX’s calling card. It premiered in Philadelphia in 2014 and has regularly toured around the country. It is a rich tapestry of a piece with four musicians each playing many instruments on the stage, and the dancers sometimes singing along.

Sunset, o639 Hours is the story of the first airmail flight between the United States and New Zealand in 1938 — 4,000 miles across open water. It is a tale of daring adventure, longing for people so far away, and then tragedy, when Captain Edwin Musick’s plane exploded midair on a second flight to New Zealand.

The emotions feel familiar more than 80 years later during this pandemic — distance and loss. The dancing, the music, the story draw in audience members.

Only a few dancers remain in the company from the 2014 world premiere, but one of them is Zachary Kapeluck, who reprised the role of Musick in a sublime partnership with Francesca Forcella, as his wife.

The dancers become the plane, their bodies vibrating with the engine. They swoop as birds. They celebrate New Year’s with a swing dance, beat out the rhythms of American Samoa during a layover, and do a stylized hula on a stop in Hawaii. Ashley Simpson, who joined the company last year, shows off her acting chops along with her dancing, even when she’s in the background.

In the middle of success and celebration, there’s an awful screech of metal in the fated plane. The lights dim and the dancers are underwater. One “floats” over a series of others rolling on what is supposed to be the sea floor.

Letters from the mail plane meant for New Zealand are read aloud. Letters upon letters upon letters that will never reach their destination.

Forcella walks slowly and desperately across the stage and into a ghostly and gorgeous pas de deux with Kapeluck, stretching, leaning on, and longing for her late husband.

The movement is stark and the loss achingly raw. And we, the masked audience can feel it, too.

DANCE REVIEW

BalletX

8 p.m. Friday, 2 and 8 p.m. Saturday, 2 and 7:30 p.m. Sunday. Suzanne Roberts Theater. $60-$70. Information at 215-225-5389 x250 or balletx.org.