
...except everybody's wearing
the same COSTUME: Indian Guy.
The Big Bang Theory Season 4, Episode 7

PRIYA: I can't believe I'm wearing
my brother's Halloween COSTUME.
The Big Bang Theory Season 4, Episode 24

to have a COSTUME meeting.
The Big Bang Theory Season 12, Episode 24

to wear the French
maid's COSTUME.
The Big Bang Theory Season 5, Episode 21

and showing up
at a COSTUME party
The Big Bang Theory Season 12, Episode 5