|Original Airdate||December 17, 1999|
|Written by||Matthew Nelson|
|Directed by||Fred Savage|
|Guest starring||Jeff Menell as Street Santa, Blake Clark as Chet Hunter|
Alan is always very excited about his surprise birthday party, and this year is no exception. Eric has been nominated to help plan, although his plans are half-baked. He thinks Alan will torture to get information, so he requires everyone to be prepared for that. So, Eric talks with Cory, Topanga, Amy, and Morgan about his plans as Alan enters. Alan is excited, dropping hints left and right. Shawn enters with Angela, and he's got news. He's recieved a letter from Virna, his mom. Apparently, she's not his birth mother. A while later, Jack helps Shawn research his family tree to find his mom on the internet. He's narrowed it down to a woman named Elaine McGinty, and Jack an e-mail to get confirmation. Eric, though, has other concerns. He plans to poison Morgan as a distraction before his father's party, and get pony rides just in case she dies. This terrifies Cory and Topanga.
Days later, Eric prepares Rachel for his dad's surprise party by explaining an odd caper where she yells, "The Japanese are attacking!" Cory, Topanga, Angela, and Jack watch, but no one can really believe how stupid Eric is, and Shawn enters with an envelope. He opens it, and it reveals that Elaine is not his mother. At a dead end, Shawn faces a crisis. Everyone tells him that it'll be okay, and Shawn seems to accept that, but he wanders off alone. Angela, Cory, and Topanga agree that he'll do something destructive.
At the Matthews' house, Alan is depressed because he didn't make plans for that night because he thought there'd be a party. Eric tells him there isn't, but not to make plans for the following night. Just as this peaks Alan's interest, everyone jumps out and yells "surprise!" Amy reveals that they used Eric as a decoy because he is stupid. Shawn then enters, stumbling drunkenly. Cory and Angela both separately try and fail to pull him aside to talk. When Alan sternly tells Shawn to come into the kitchen to talk, Shawn begins to ramble about how he is an orphan and has no parents. Alan offers to adopt him as his son, but Shawn simply leaves.
As Shawn wanders down the street, he senses a person behind him. He turns around to tell Cory to go home, but it isn't Cory, it is a man dressed as Santa Claus. Shawn drops a buck, and the Santa walks away, revealing Cory behind him. Cory urges Shawn to return to his home, but Shawn insists on going to the cemetary, to see his own family. He goes there alone, and begins talking to his father's grave. Chet appears, and the two begin to talk. Chet says that Virna is his real mother, even if she didn't give birth to him. His actual mom was a stripper, but she left as soon as Shawn was born. Chet tells Shawn he comes from a long line of lousy, and to hold on to those he loves, such as Angela and Cory. Cory shows up, and Shawn agrees that it is time to return to the party.
Apologetic, Shawn holds out his gift to Alan. It is a ceramic cast of his handprints, and Alan says he'll cherish it. Shawn request that Alan yells at him like he does with Cory and Eric, and Alan obliges. Alan tells him not to do these things, because it scares those who love him. Shawn promises he won't.
- At the beginning of the episode, Cory states that Alan was a cook at the Coast Guard, but during one of the earlier seasons Alan gives Cory a pair of little silver mittens that he says he won them during a navy Boxing competition.
- Chet was married 62 times.