Deb was born in Moose Jaw, Saskatchewan but spent her formative years in Esterhazy, Saskatchewan (potash capital of the world) where her father served as the mayor and local mortician. She graduated from the University of Saskatchewan and relocated to Toronto where she became a member of Second City’s resident Company. During her years onstage there, she won a Dora (Canada’s equivalent of the Tony) for writing and performing in “Not Based on Anything by Stephen King”. She starred alongside Joe Flaherty in the critically-acclaimed Lucasfilm series Maniac Mansion (1990), which TIME magazine hailed as “a comic gem”. Deb also wrote for the series, a quirky satire about genetic mutation which was the brainchild of Eugene Levy and George Lucas. She was nominated for a Cable Ace Award as Best Actress in a Series for her work on the snow. Deb is a versatile character actress who has appeared in four features and multiple commercials for writer/decorator Christopher Guest, who saw her perform with The Second City Los Angeles cast in 1990 and recommended her for the lead in the Norman Lear project her was writing. Deb is a longtime collaborator of The Kids in the Hall and co-wrote Scott Thompson’s Comedy Central special and co-wrote and directed two solo stage shows for him. She has appeared in two films and multiple pilot projects for writer/director Ash Christian and won the Best Supporting Actor award at QFest in Asheville, NC in October 2011 for her role as a predatory beautician in Christian’s film Mangus. She was nominated as Best Supporting Actress opposite Mickey Rooney and Louis Mandylor in Mark Clebanoff’s film Gerald in 2010, in which she aged from 35 to 70.
Theaker has made numerous television appearances, most memorably as a sweet serial killer on Bones, a disturbed psychic on Reno 911, and the unscrupulous thieving caterer on Curb Your Enthusiasm whom Larry fights for the leftovers. She appears on film in A Mighty Wind as Naomi Steinbloom, in Lemony Snicket as Polly Poe, and in Abe Sylvia’s Dirty Girl as a sexually-repressed special-ed teacher. Sylvia gave her free rein to improvise her role as a sex educator. She was the head of a gang of Lucy impersonators in Jerry Zucker’s classic comedy Rat Race (2001). She is a favorite of gifted commercial director Bryan Buckley, recently appearing in TBS trailers for CSI as a coroner, eating intestine-like noodles in a morgue while watching CSI.
Off-camera, Deb is a gifted visual artist and designer.