So THAT'S why Blaine and Rachel were all gussied up!
Last week, the Glee crew were spotted at the Walt Disney Concert Hall filming a beautiful musical number for the show and now we know what they're up to!
Lea and Darren shared their sentiments about performing Broadway Baby together and surprise! Whoopi Goldberg makes an appearance at this performance!
Ch-ch-check them gushing over their duet (above)!