The CLUE must be
in the bag.
The Big Bang Theory Season 7, Episode 3
Okay, the CLUE
must be in the bag.
The Big Bang Theory Season 7, Episode 3
There's got to be a CLUE
here somewhere.
The Big Bang Theory Season 12, Episode 2
I'm gonna need
another CLUE.
The Big Bang Theory Season 7, Episode 18
The sole CLUE:
"It's not what it looks like."
The Big Bang Theory Season 5, Episode 1