Tonight's obstacles include the Trippity Skippity Flippity Doo. 'Nuff said.
Elsewhere on TV ...
Project Runway (7 and 11:02 p.m., Lifetime): Contestants have to create looks that include a bow tie.
Big Brother (8 p.m., CBS/Ch. 2): The head of household competition.
Motive (8 p.m., ABC/Ch. 4): An art collector is killed.
And the Winner Is … (8 p.m., NBC/Ch. 5): The last episode of this little-watched game show.
Rookie Blue (9 p.m., ABC/Ch. 4): There's a robbery on a casino-bound bus.
Sullivan & Son (8 and 10 p.m., TBS): Ok Cha injures her leg in a car accident.
Hollywood Game Night (9 p.m., NBC/Ch. 5): Celebrities play parlor games.
Sharkpocalypse (10 p.m., Discovery) and Alien Monster Sharks (11 p.m., Discovery): Shark Week continues.