On the cusp of turning 100 on Saturday, TV legend Dick Van Dyke gets the “American Masters” treatment in the new PBS film “Starring Dick Van Dyke” (9 p.m. Dec. 12, WQED-TV).

The two-hour documentary offers an entertaining career retrospective that’s also full of surprises, including:

• CBS initially canceled “The Dick Van Dyke Show,” now seen as an early TV comedy masterpiece.

• Van Dyke once hosted a CBS morning show where Walter Cronkite was the news anchor.

• Van Dyke got his start as part of a comedy duo, The Merry Mutes.

“Starring Dick Van Dyke” filmmaker John Scheinfeld (“The U.S. vs. John Lennon”) digs deep, mining little-seen archival interviews paired with new interviews with bold-faced names, including Carol Burnett, Jim Carrey, Ted Danson, Steve Martin, Conan O’Brien and Martin Short.

In a Zoom interview last week, Scheinfeld said there’d never been a definitive documentary on Van Dyke’s career, particularly through the prism of Van Dyke as an actor who successfully reinvented himself repeatedly to remain relevant.

“Today we see some stars of movies and TV shows who haven’t done the work for years to develop their talent and sometimes they flame out quickly, and sometimes they do end up developing it,” Scheinfeld said. “But what we saw with Dick is right from the beginning, there were a series of steps that he took, no one of them more important than the other, but each contributed to developing his talents, so that when ‘The Dick Van Dyke Show’ opportunity presented itself, he was ready. And that’s why he kind of seemed to burst on the scene then.”

Part of Van Dyke’s background included utilizing the tools of silent film stars, particularly physical humor (e.g., tripping over the futon in the “Dick Van Dyke Show” opening credits).

“Steve Martin and Ted Danson talk about that physical humor that is such an important part of Dick’s artistry,” Scheinfeld said. “Dick himself in the film talks about how he was influenced by Stan Laurel, by Buster Keaton.”

In addition to Van Dyke’s work in comedies and musicals (“Bye Bye Birdie,” “Mary Poppins”), the film shows his versatility, from playing an alcoholic in a 1970s TV movie (“The Morning After”) to his eight-year stint as the star of the CBS mystery procedural “Diagnosis: Murder.”

“To see Dick doing this gritty, dark role [in ‘The Morning After’] was quite a shock for the fans,” Scheinfeld said.

Van Dyke was also an early supporter of Martin Luther King Jr. and the Civil Rights Movement. He read a speech written by Rod Serling (“The Twilight Zone”) from the same stage as King in Los Angeles in 1964.

“We took a very deep dive, and we were able to find the daughter of a photographer who had taken a number of photographs at that event,” Scheinfeld said.

He hopes the documentary cements “just how much joy and inspiration he gave people with the work that he did. … This is a portrait of an artist that is worthy of being right up there in the top echelon.”

‘Happiness’

It’s difficult to imagine a better, more unexpected holiday gift than PBS’s “Happiness,” a rare PBS comedy that’s pretty much “Schitt’s Creek” meets “Smash.”

Airing Sundays at 10 and 10:30 p.m. Dec. 14-28 on WQED-TV – way too late; PBS intends the show to air at 8 and 8:30 p.m., which makes more sense for family co-viewing given the “Glee” of it all – this import from New Zealand charms from start to finish. (“Happiness” also streams at PBS.org, on the PBS app and via PBS Masterpiece on Prime Video.)

Broadway director Charlie Summers (Harry McNaughton) gets welcomed back to New Zealand at the airport by a “Backstreet Boys”-themed flashmob orchestrated by his mother (Rebecca Gibney), head honcho at a community theater that’s about to stage “The Trojan Horse: A New Musical.”

Much to his chagrin, Charlie ends up pitching in on the production, which is stocked with an array of clearly defined characters effortlessly introduced with a bare minimum of exposition, a rare feat in a pilot episode.

Fast-moving and funny, “Happiness” embraces and sends up theater tropes, including a Napoleonic director who tries to reassure his cast but fails, saying, “Now is a time for unity and cohesion and doing what I say.”

Created by Kip Chapman and Luke Di Somma, “Happiness” introduces a raft of catchy original tunes from “Trojan Horse,” available for digital download via Spotify. Tell the theater kid in your life about this show. It’s 100% for them.

Created originally for HBO Max Australia, this PBS airing is the first time “Happiness” will be available in the U.S. A second season is in the works and PBS will air it next year.

Third ‘Knives Out’

The third “Knives Out” mystery, “Wake Up Dead Man,” may be the best yet.

Streaming Dec. 12 on Netflix after a brief theatrical run, this third outing with detective Benoit Blanc (Daniel Craig) improves on the disappointing second installment, forgoing massive, James Bond-worthy sets in favor of a smaller, more intimate story with themes of belief and redemption in a culture where too many are energized by conflict and accusation.

Josh O’Connor (“God’s Own Country”) stars as Father Jud, a junior priest with a tragedy in his past who becomes ensnared in a small church community’s secrets and lies, presided over by a fire-breathing monsignor (Josh Brolin) who preaches vengeance-seeking homilies.

Writer/director Rian Johnson crafts this “Knives Out” as an ode to faith and grace and an antidote to strains of Christianity that defy WWJD proscriptions.

The film benefits from a top-tier cast that includes Glenn Close – giving a Cloris Leachman vibe in the early going – alongside Kerry Washington and Jeremy Renner (“Mayor of Kingstown”).

But it’s the two-hander appeal of O’Connor’s earnest-but-human portrayal of a priest in crisis paired with Craig’s rascally sleuth that makes “Dead Man” feel most alive.

Channel surfing

The 10-episode fifth season of “Emily in Paris” debuts on Netflix Dec. 18. … NBC named Sheinelle Jones co-host of the fourth hour of “Today” alongside Jenna Bush Hager. … Matt Gutman jumped from ABC News to CBS News, where he’ll be chief correspondent. … Status.com reports CBS will name Tony Dokoupil the next anchor of “CBS Evening News.”