Just so you know, Mac and D.B. met before — at some work shindig, where somebody covered Freddy Mercury with a karaoke machine, which prompted a local to hurl chicken wings.

But for the purposes of the CSI and CSI: New York fans, this will be the first time Mac (Gary Sinise) and D.B. (Ted Danson) meet on camera. Here’s a sneak peek of the crossover episode that starts on CSI tomorrow at 10 p.m. and ends on CSI: NY this Friday.