LEONARD EXPERIMENTS WITH BEING A "BAD BOY," WHILE SHELDON TRIES TO SPOOK HIS FRIENDS ON HALLOWEEN, ON "THE BIG BANG THEORY," THURSDAY, OCT. 27

"The Good Guy Fluctuation" - A cute comic book artist puts Leonard and Priya's relationship to the test, while Sheldon tries to scare the guys for Halloween, on THE BIG BANG THEORY, Thursday Oct., 27 (8:00 - 8:31 PM, ET/PT) on the CBS Television Network.

SERIES REGULARS:

Johnny Galecki (Leonard)
Jim Parsons (Sheldon)
Kaley Cuoco (Penny)
Simon Helberg (Wolowitz)
Kunal Nayyar (Koothrappali)
Mayim Bialik (Amy)
Melissa Rauch (Bernadette)

RECURRING CAST:

Aarti Mann (Priya)
Kevin Sussman (Stuart)

GUEST STARS:

Courtney Ford (Alice)

STORY BY: Chuck Lorre, Dave Goetsch and Maria Ferrari

TELEPLAY BY: Bill Prady, Steven Molaro and Steve Holland

DIRECTED BY: Mark Cendrowski

RATING: To Be Announced