Terry Lake (portrayed by Sabrina Lloyd) was a forensic psychologist and often acted as a profiler for Don Eppes' FBI team.
Robert Bianco of USA Today considered Lloyd a standout in the supporting cast but criticized the characters making up Don's team as lacking in originality.
[2] Dr. Mildred ("Millie") Finch (portrayed by Kathy Najimy) is the newly appointed Chair of the CalSci Physics, Mathematics, and Astronomy Division, and an experimental neutrino astrophysicist who worked on the construction of AMANDA.
Being lighthearted, she has made a bet with Alan on who can go longer without using consumer products and has even helped him with his lawsuit by showing that his design specifications were not met.
She is a fan of James Bond films and took a three-month sabbatical from MIT to sail the South Pacific with a friend.
CalSci recruit Oswald Kittner (Jay Baruchel) warmed to her, making his decision to become a student easier.
According to actress Kathy Najimy, Millie is a smart, independent woman who does whatever it takes to get the job done and does not like pursuits of goals contrary to her mission.
[3] Millie was developed as a recurring character to serve as a scientist interested in advancing women's position in science and as Alan's potential girlfriend.
It is heavily implied in "Two Daughters" and "Pandora's Box" that Ian used interrogation techniques, including physical force and borderline torture, to get information from a teenage accomplice of Crystal Hoyle.
Edgerton returned for the season six finale in a cameo appearance where he made an arrest and expressed disappointment that he was not invited to Charlie and Amita's wedding.
[8] Lt. Walker (portrayed by Will Patton) is an officer of the Los Angeles Police Department, normally working on cases involving gang violence and organized crime.
He appeared four times, beginning in Season 2 during the episode "The O.G.." In an interview with IGN.com's Travis Fickett, creator and executive producer Cheryl Heuton said that the cast and crew enjoy working with Patton.
[9] For the episode "Hardball", series executive producers/co-creators Nicolas Falacci and Cheryl Heuton created Oswald to represent the geniuses who fail to receive a formal education.
[11] Heuton and Falacci developed the character of Oswald Kittner for another friend of series regular David Krumholtz.
After seeing Baruchel's performance, Heuton and Falacci modified the role to include some humorous lines and add Oswald's voice.
Oswald also receives two job offers, one from the FBI to develop his equation as an investigative tool and one as a statistician with the minor league team.
[8] Assistant United States Attorney Robin Brooks (portrayed by Michelle Nolden) is a recurring character on the American television show Numb3rs.
Actor Rob Morrow asked the producers to explore Don Eppes's personal life, which included his romantic relationships.
[15] Michelle Nolden, who had previously starred in Showtime's Street Time as the wife of Morrow's character,[14] was cast as Brooks.
He serves as a foil for Charlie with his apparent genius, ability to get completely lost in his work, and early uneasiness with criminal violence.
As Larry takes over Charlie's FBI responsibilities for his leave to Cambridge, the enthusiastic Otto serves as assistant to Dr. Fleinhardt.
Professor Russell Lazlo (portrayed by Tony Hale) is an eccentric CalSci geneticist who appears in the season six episodes "Hydra" and "Devil Girl."
Roger Bloom (portrayed by Henry Winkler) is an FBI agent who first appeared in the episode "Jack of all Trades."
He reappears in the episode "Greatest Hits," where we are informed that he was forced to leave the agency due to the events in "Jack of all Trades."