Gussis joined the crew of Showtime drama series Dexter as a staff writer for the first season in 2006. Gussis was nominated for a Writers Guild of America Award for best dramatic series at the February 2008 ceremony for her work on the first season of Dexter.[2][3][4] She was promoted to story editor for the second season in 2007 and continued to script episodes. She joined the productions staff as a co-producer for the third season in 2008. She was again nominated for the WGA award at the February 2009 ceremony for her work on the third season of Dexter.[5] She was promoted again to producer for the fourth season in 2009. She was nominated for the WGA award a third consecutive time at the February 2010 ceremony for her work on the fourth season.[6] She was promoted again to supervising producer for the fifth season in 2010.