Turner Classic Movies offers a three-film festival of thrillers featuring hard-boiled detective Mike Hammer, beginning with “Kiss Me Deadly” (7 p.m., TCM) starring Ralph Meeker. Cloris Leachman appears in a supporting role in this movie from 1955.

Just how long has Cloris Leachman been acting?

Her remarkable career includes an Oscar for the drama “Last Picture Show” (1971) and unforgettable roles in Mel Brooks comedies, most notably “Young Frankenstein” (1974).

But television has been where Leachman has been working. And working. Even more than the beloved Betty White, Leachman has been an essential part of television throughout the medium’s entire history. A cursory glance at her list of credits presents a snapshot history of the small screen.

Years before most Americans even owned a set, Leachman appeared on “The Ford Theatre Hour” in 1948! She’d go on to star on dozens of shows — many now forgotten — during television’s first decade. She’d make only one appearance on “The Twilight Zone,” but it was an indelible one, as the terrified mother of an all-powerful destructive brat (Billy Mumy) in the 1961 episode “It’s a Good Life.”

Throughout the 1960s, she’d make single or multiple appearances on “The Untouchables,” “Route 66,” “Wagon Train,” “Alfred Hitchcock Presents,” “77 Sunset Strip,” “The Defenders,” “Dr. Kildare,” Perry Mason,” “Run for Your Life,” “Adam-12,” “The Name of the Game,” and “Ironside.” And those are only the well-known series!

It’s a long, long time from the period of Uncle Miltie and Sid Caesar’s “Your Show of Shows” to “American Idol.” But Cloris Leachman has been a part of television through every decade and every era. And she’s not just a novelty act or a comeback kid. She’s an essential part of the chemistry of “Raising Hope.”

No one person could ever embody the vast scope and history of television entertainment. But if I had to choose just one, It would have to be Cloris Leachman.

• “Flashpoint” (7 p.m., CBS), the competently made Canadian drama about a special unit devoted to handle hostage and sniper crises, returns for a new summer season.

Tonight’s other highlights

• Coach mediates a locker room brawl and Luke fields offers on “Friday Night Lights” (7 p.m., NBC).

• An Italian restaurant seems caught between Avanti! and Basta! on “Kitchen Nightmares” (7 p.m., Fox).

• Almost a bridge too far on “American Loggers” (7 p.m., Discovery).

• A crime lab becomes a crime scene on “CSI:NY” (8 p.m., CBS). Peter Fonda guest stars.

• Peter looks destiny in the eye on the third season finale of “Fringe” (8 p.m., Fox).

• Suspicion falls on a son after family friends of the Reagans are slain on “Blue Bloods” (9 p.m., CBS).

• Craig Morgan and Brett James guest judge on “CMT’s Next Superstar” (9 p.m., CMT).

• Guinevere takes a trip “Camelot” (9 p.m., Starz).