We’ve got a number of casting additions for the small screen today. First up, Malin Akerman (Watchmen) will be joining Portia de Rossi (Arrested Development) in the ABC comedy, The Smart One. Written by Don Todd (Ugly Betty), The Smart One follows a brilliant and successful woman (de Rossi) who goes to work for her popular, but less intelligent sister (Akerman).Eamonn Walker (Oz) is the first actor to be cast in NBC’s Dick Wolf (Law & Order) drama pilot, Chicago Fire, which follows the heroic men and women of the Chicago Fire Department. Finally, from the CW comes Arrow, the television series following the exploits of DC Comics’ Green Arrow. Katie Cassidy (Monte Carlo) has been cast as the female lead opposite Stephen Amell (Private Practice). Hit the jump for more on each project.Deadline reported on Akerman joining The Smart One. Starring as a former beauty queen and weather girl, Akerman will portray a big city mayor who hires her braniac sister to work for her. Jean Smart (Harry’s Law) has also been cast as the mother of the two sisters. Akerman can next be seen in Wanderlust and Rock of Ages. Deadline also reported on Walker’s addition to Chicago Fire. Walker will play Walter Boden, a former Golden Gloves champ who became chief of the department, but is now considering retirement. The pilot, directed by Jeffrey Nachmanoff (Homeland), comes from a script by Wanted writers,  Derek Haas and Michael Brandt.Finally, Deadline reported on Cassidy’s addition to the Arrow cast for the CW. Starring as Laurel, a young legal clinic attorney who shares a romantic past with Oliver Queen (Amell), Cassidy may eventually be playing the dual role of Black Canary (in the comics, Dinah “Laurel” Lance was the mild-mannered alter ego of the superhero). Cassidy joins Susanna Thompson (Dragonfly) who was recently cast as Oliver's mother, Moira Queen.