Grey's Anatomy swung and hit a grand slam this week, airing one of the more fun episodes of season eight. Read our review of "Put Me In, Coach" HERE.

But we hope you enjoyed your guffaws, fans, because things get serious and nostalgic next Thursday when George O'Malley's mother, Louise, visits Seattle Grace following a botched surgery elsewhere. Watch the official ABC trailer for "Heart-Shaped Box" now.

What else can fans expect from the upcoming hour?

• The residents actually witness a harvested heart... that somehow continue to beat outside its body.
• Arizona gets excited over a new pediatric fellow, while Alex feels threatened.
• Jackson runs into problems in his professional due to suspicions about Mark and Lexie.
• Henry and Teddy engaged in their first fight as a married couple.