Laird Cregar was educated at Winchester College in England, spending his summers as a page boy and bit player with the Stratford-upon-Avontheatrical troupe. Upon completing his schooling, Cregar won a scholarship at California's Pasadena Playhouse, supporting himself as a nightclub bouncer when funds ran out. So broke that at times he had to sleep in his car, Cregar forced Hollywood to pay attention to him by staging his own stage vehicle, Oscar Wilde by Leslie and Sewell Stokes, in which Cregar played the title role.
After a few minor film roles, Cregar was signed to a 20th Century-Fox contract; among his first major roles was the middle-aged Francis Chesney (at the age of only 24) in Charley's Aunt (1941), the first of several showcases for the actor's delightful comic flair. With his sinister portrayal of the psychopathic detective in I Wake Up Screaming (1941), he followed that up with the successful screwball comedy Rings on Her Fingers(1942) playing a con artist opposite Gene Tierney. Cregar became one of filmdom's top "heavies" — both figuratively and literally. Seldom weighing less than 300 pounds (136 kg) throughout his adult life, Cregar became obsessed with his weight.
After top billing in The Lodger (1944), who may or may not be Jack the Ripper, the increasingly sensitive Cregar was growing tired of being thought of as merely a hulking villain.
When assigned the role of demented pianist George Bone in Hangover Square (1945), Cregar decided to give the character a "romantic" veneer, and, to that end, lost more than a hundred pounds on a crash diet which included prescribed amphetamines. The strain on his system resulted in severe abdominal problems; a few days after undergoing stomach surgery, Cregar died of a heart attack. He was 31 years old. Hangover Square was released two months after his death.
Cregar was laid to rest in a simple grave beside the road in the Eventide Section, at Forest Lawn Memorial Park in Glendale, California.