Via Botany Photo of the Day, Basilio Aristidis Kotsias makes the case that Claudius could indeed have poisoned King Hamlet by instilling henbane into his ear. And yet,
There are other explanations that fit the crime in question….. Finally, there exists the possibility that everything related to the apparition of the ghost on the platform before the castle of Elsinore was a product of Shakespeare’s fantasy, as well as the death of the melancholic prince, wounded by the poisoned sword (with what venom?) that Laertes held. If this were true, our interpretation would result in pure fiction.