Rain will make a rare appearance in the upcoming “Lotte Card MOOV Soundtrack” concert on Sept. 29.

Lotte Card said Friday that Rain will star in the concert at Olympic Gymnastics Arena as part of the company’s music collaboration project.

The official poster features the singer on the top half with the question, “And Who?” at the bottom, drawing speculation as to who will star alongside Rain on the stage.

(Lotte Card)

Rain is one of the two artists to be unveiled for this year’s MOOV Soundtrack concert, which brings two artists of different styles together to create a unique artistic chemistry each year.

In 2016, singer-songwriter Shin Seung Hun and J.Y. Park performed together for the very first such concert.

In the following year, pop heavyweight Seo Taiji and BTS delivered a joint performance in celebration of the 25th anniversary of Seo’s debut.

By Yim Hyun-su (hyunsu@heraldcorp.com)