PARTIESPhotos: Saturday Night on ThursdaySteven Alan celebrates a new book about SNL.by Sarah Leon03.06.151Alison Castle and Steven Alan. Photo by BFAnyc.com.2TK Wonder. Photo by BFAnyc.com.3Edie Baskin and Mary Ellen Matthews. Photo by BFAnyc.com.4Fred Armisen. Photo by BFAnyc.com.5Steve Higgins and Colin Jost. Photo by BFAnyc.com.6Hannelore Knuts, Angelo Apollo, and Nicolas Provost. Photo by BFAnyc.com.