Sir Michael Caine was so very much beside himself to be working with Lord Laurence Olivier that he didn't even know how to address him. Eventually, he broke down and just asked. Olivier replied "Well, I am the Lord Olivier and you are Mr. Michael Caine. Of course, that's only for the first time you address me. After that I am Larry, and you are Mike."
The photograph raised up the wall to replace the one shot by Andrew is of famed mystery author Dame Agatha Christie.
Michael Caine tells in his biography that Laurence Olivier could not, at first, remember his lines - he, a great stage actor who could initially remember three hours of lines in a play. He could not because of pills he started taking to calm him down after he learned that a theater of his, which he put much money and many efforts in for many years, had to be closed down. But Olivier eventually stopped taking those pills and his memory issues stopped.
The two London street name signs in Andrew's cellar are references to crime mysteries: Baker Street was the fictional residence of Sherlock Holmes, and Berner Street was the real-life scene of a Jack the Ripper murder.