With The First Evil making up the bulk of Part 1's inspiration, The Surprise Party has more to do with character motivations. A year after Evan dies in the Fear Street woods and Ellen moves away, Meg plans a surprise party to get the gang back together. Eventually, Meg begins receiving ominous threats to cancel the party unless she's able to discover the truth the Fear Street woods hide.
Part 1's Sam is very much like Ellen, in the way that they both move away after a traumatic event. For Ellen, it's her boyfriend's death, and for Sam, it's the divorce of her parents. Ellen and Meg drifted apart after the move, while Sam and Deena broke up because of it. Then there's the character of Brian in The Surprise Party, Meg's cousin who is very into Dungeons and Dragons. In Part 1, Deena's brother Josh, who is very into video games and chatting on the internet, seems to take up the "weird" mantle that was given to Brian.
