In the restaurant scene with Banacek & Carly, which takes place at "Anthony's Pier 4," owner/restaurateur Anthony Athanas makes a brief cameo appearance in which Banacek shakes his hand and calls him "Tony" and later states that he's Albanian-American.
Kirkland makes snide comments about Gretel's age and youth, when, in fact, Kirkland is 2 years *younger* than Gretel.
Insurance executive Cavanaugh is mentioned (as being on vacation) but unseen.
Out by the pond, when Jay relates his theory of how the statue was stolen, he refers to a book theft in a previous Banacek episode, Ten Thousand Dollars a Page (1973), spoiling that episode's solution in the process.