This is the first time that the word "fuck" is said on the show.
The back of the box of Raisin Bran features an ad for a cassette of songs by the California Raisins. This started as a TV commercial promoting the California Raisin Advisory Board, using claymation raisins singing Marvin Gaye's "I Heard It Through The Grapevine." This was followed by a series of sequel TV spots plus four record albums, plus a range of retail merchandise.
Phillip left a package for Oleg to pick up at a steel wire mesh door. The site which is used for such a transaction is called a "dead drop", the point of which is avoid a in-person meeting, which would leave one exposed to detection by an enemy intelligence service.
Oleg mixed together a solution to uncover a key written in invisible ink, so that he could decode a message sent by Phillip.