ST. LOUIS - It's  a surprise no one saw coming—R&B legends, TLC crashed a performance at a St. Louis hot spot.  

This once-in-a-lifetime moment was caught on camera, and of course, it went viral.

Singer Tish Period was performing TLC’s “Waterfalls” before the group walked in. Period who's been featured on national TV before told FOX 2 nothing could prepare her for the night TLC crashed her set.

“Sunday night was just a special night. Never in a million years would I have thought that TLC—my teen-aged icons—would walk in while I was signing their songs,” Period said. “I’m honored. I believe God was going to make sure it happened to me to where I was able to see TLC.”

Others jumped on stage and joined the viral performance. 

“They were dancing, next thing you know I got Chili standing next to me looking, next thing you know, TBOZ walks in. I thought I saw a ghost. I felt like crying, I felt like shouting. I was just happy to have that experience,” Period said.