Visual pun
Immediately after the detective asks M. Hire, "When was the last time you came inside a woman?" the film cuts to a view of bird feed falling onto Hire's feet as he sits on a park bench feeding the pigeons. Spilling his seed, yes?
This pigeon scene ties into the story he tells Alice about the bird lady: is he feeding the pigeons or poisoning them? Life or death? Just like the fate of the poor little mice, a question hanging in the air.
I saw this in the theatre when it was first released in the U.S., then again on DVD this weekend. Seamless and thought-provoking.