Last cinema film acting role of John McCallum.
Rankin says "I gave him the winner of the cup two years running" in relation to Superintendent Robbins. He is referring to the winner of the Melbourne Cup, the biggest and most famous horse race in Australia.
Smiley's quote 'Then up spake Brave Horatius' is from "Horatius" by Thomas Babington Macaulay, Lord Macaulay
Two-up is an Australian gambling game. Players wager on the toss of two coins, placing money on a result of two heads or two tails. If one of each turns up, there is no result and the coins are tossed again.