The Wu-Tang pair break the news at Sundance.

Raekwon and Ghostface Killah had teased a surprise for attendees of the Utah film festival, and Rae has taken to Twitter to share the news, announcing The Purple Tape Files, a documentary about his legendary Only Built 4 Cuban Linx LP.

It’s unclear if the pair screened the documentary or just the trailer — more as we have it. Until then, check out the 20 best Wu-Tang Clan deep cuts. Update: Watch the trailer below.

Twitter It's official, I released the trailer at Sundance for our documentary #ThePurpleTapeFiles …. This is just the beginning. ..

— Raekwon The Chef (@Raekwon) January 25, 2015