Foul Is Fair

S6 E9: After learning unsettling news, Dawson (Monica Raymund) enlists Severide (Taylor Kinney) to help her out. Elsewhere, Casey (Jesse Spencer) and Dawson struggle with communication issues while Brett (Kara Killmer) and Kidd (Miranda Rae Mayo) compete to win the heart of Zach (guest star Daniel Di Tomasso), a Hazmat officer. Meanwhile, Otis (Yuri Sardarov), Herrmann (David Eigenberg) and Mouch (Christian Stolte) are on a mission to locate the source of a horrible stench that is making life unpleasant at Firehouse 51.