First Look: It's Out With The Old, In With The New On The Big Bang Theory

Bernadette and Howard prep for a night at home in the hot tub.

1. Bernadette and Howard prep for a night at home in the hot tub.

Sheldon and Amy host a live Valentine's Day episode of Fun With Flags, while Leonard and Penny grapple with getting older. Plus, Howard and Bernadette find a surprise in their hot tub, and Raj is torn between Emily and the cute girl he met at the comic-book store on the next episode of The Big Bang Theory entitled "The Valentino Submergence."
Howard and Bernadette spot something floating in the hot tub.

2. Howard and Bernadette spot something floating in the hot tub.

"The Valentino Submergence" (Episode 15, Season 9 of The Big Bang Theory)
 
Bernadette fishes something out of the hot tub.

3. Bernadette fishes something out of the hot tub.

"The Valentino Submergence" (Episode 15, Season 9 of The Big Bang Theory)
Bernadette cuddles the couple's surprise guest.

4. Bernadette cuddles the couple's surprise guest.

"The Valentino Submergence" (Episode 15, Season 9 of The Big Bang Theory)
Bernadette and Howard share a tender moment in their robes.

5. Bernadette and Howard share a tender moment in their robes.

"The Valentino Submergence" (Episode 15, Season 9 of The Big Bang Theory)
Howard feeds the bunny he and Bernadette recently found in their backyard.

6. Howard feeds the bunny he and Bernadette recently found in their backyard.

"The Valentino Submergence" (Episode 15, Season 9 of The Big Bang Theory)
Penny and Leonard have a tiff at a restaurant.

7. Penny and Leonard have a tiff at a restaurant.

"The Valentino Submergence" (Episode 15, Season 9 of The Big Bang Theory)
Raj confides in Leonard, Howard, and Sheldon about his girl troubles.

8. Raj confides in Leonard, Howard, and Sheldon about his girl troubles.

"The Valentino Submergence" (Episode 15, Season 9 of The Big Bang Theory)
Amy and Sheldon host a new episode of Fun With Flags.

9. Amy and Sheldon host a new episode of Fun With Flags.

"The Valentino Submergence" (Episode 15, Season 9 of The Big Bang Theory)
Amy and Sheldon have some troubles filming their web series.

10. Amy and Sheldon have some troubles filming their web series.

"The Valentino Submergence" (Episode 15, Season 9 of The Big Bang Theory)
Amy is confused by Sheldon's intriguing flag.

11. Amy is confused by Sheldon's intriguing flag.

"The Valentino Submergence" (Episode 15, Season 9 of The Big Bang Theory)
Sheldon's enthusiasm fades as Fun With Flags becomes a therapy session for Raj.

12. Sheldon's enthusiasm fades as Fun With Flags becomes a therapy session for Raj.

"The Valentino Submergence" (Episode 15, Season 9 of The Big Bang Theory)

Watch all-new episodes of The Big Bang Theory on Thursdays at 8/7c.