A woman who can grow a beard at will and is a member of the Cirque Du Freak. She is the one who gave Darren his costume for the show.
In the 'Lake of Souls' she says that her husband and daughter were killed by an evil fisherman. When we go on to read the book, Darren and Harkat come across a pirate fisherman called Spit Abrams who is a cannibal. So it could be that Truska's husband and daughter were killed, cooked and eaten by Spits.
In the movie, she will be played by Salma Hayek.