Nicole de Boer is a Canadian actress. She is known for starring in the cult film Cube as Joan Leaven, playing Ezri Dax on the final season of Star Trek: Deep Space Nine (1998–1999), and as Sarah Bannerman on the series The Dead Zone (2002–2007). Nicole de Boer is a Canadian actress. She is known for starring in the cult film Cube as Joan Leaven, playing Ezri Dax on the final season of Star Trek: Deep Space Nine (1998–1999), and as Sarah Bannerman on the series The Dead Zone (2002–2007).