'This Is Us': Giving thanks for NBC's wondrous hit

In this holiday season, NBC's "This Is Us" is a show to be thankful for. This poignant, risk-taking drama is a rarity for broadcast TV, which usually sticks to crime, court and medical stories.

Family dramas are harder to pull off, and yet, "This Is Us" has become an unexpected hit at 9 p.m. Tuesdays.

The wonderful wrinkle is the show's structure. "This Is Us" jumps back and forth through time to demonstrate how the past affects current life.

"This Is Us," created by Dan Fogelman, tells imaginative stories that play like puzzles. Viewers see how different generations deal with similar issues and how childhood shapes adults. A family trip to the swimming pool years ago still marks grown children. A love for the Pittsburgh Steelers unites generations.

When "This Is Us" debuted in September, the pilot was a high-wire act. Jack (Milo Ventimiglia) and Rebecca (Orlando's Mandy Moore) were awaiting the birth of triplets. When one baby didn't survive, the couple adopted an abandoned black child.

The series depicts the children as adults: Kate (Chrissy Metz) is struggling to lose weight and find purpose. Actor Kevin (Justin Hartley) abandons a successful sitcom to try the stage. Randall (Sterling K. Brown), the adopted child, has monetary success and a loving family but questions his heritage.

Succeeding episodes have stayed up on that high wire with surprising dexterity. "Your family's amazing," a Thanksgiving guest told Kevin this week.

And so it is. Other family dramas have been about wealth ("Downton Abbey"), serial scheming ("Dallas," "Dynasty") and business ("The Sopranos"). "This Is Us" focuses on family interactions and how they reverberate. It's lighter than "Parenthood" but not as whimsical as "Gilmore Girls."

Ventimiglia, who acted on "Gilmore Girls," is a revelation as the charismatic father. Moore is doing the best work of her career. Metz, Hartley and Brown all portray vulnerability without turning maudlin.

The Thanksgiving episode explored the family's long-ago established traditions, current resentments and difficult stabs at forgiveness. In telling those stories, the show offers a sense of wonder that's breathtaking.