The most unexpected thing about the new melodrama “Life Unexpected” (8 p.m., CW) is that it’s actually good.

“Life” succeeds not by breaking new ground but with creative recycling. Next to amnesia, one of the most hackneyed stories in TV history is the notion that a confirmed bachelor is confronted with sudden, instant paternity and shocked into recognition of fatherhood by the presence of a teenager (almost always female and always pretty) at his front door.

“Life” begins in that exact fashion and then shakes things up with a few plot twists and character traits lifted from “Gilmore Girls,” “Sleepless in Seattle,” “Veronica Mars” and “Juno.”

Lux (Brittany Robertson) is 15 going on 37 and fed up with her life in foster care. She wants to emancipate herself and needs the signatures of her biological parents.

That father, Nate (Kristoffer Polaha), goes by the name Daze. He runs a bar and lives above it, and spends his down time getting high and watching sports with his 30-something unmarried pals. But Daze awakens from his haze when Lux shows up.

This chance encounter reconnects him with Cate (Shiri Appleby, “ER”), a one-night stand who gave Lux up for adoption after hiding her pregnancy in high school. She happens to be the co-host of the hottest morning talk radio show in town. Lux is a big fan and appears to have inherited her gene for sarcasm and snark.

As you might expect, all three make an instant connection, a matter complicated by the fact that commitment-phobic Cate has just become engaged to her boyfriend/co-host.

• Observances of the Martin Luther King holiday include “Obama’s America: 2010 and Beyond” (9 p.m., MSNBC), a conversation about race hosted by Chris Matthews. Tom Brokaw hosts “American Character Along Highway 50” (7 p.m., USA), a survey of contemporary attitudes. Roland Martin hosts “Living the Dream: An Interview with President Barack Obama” (7 p.m., TV One).

• An avalanche of new cable series include:

A teen lives out his dream on the kid-friendly sitcom “I’m in the Band” (6 p.m., Disney XD).

Hockey players vie for boy-band fame on “Big Time Rush” (7:30 p.m., Nickelodeon).

“American Pickers” (8 p.m., History) follows two men who scour the attics, barns and Dumpsters of this great nation to discover relics and antiques.

Tonight’s other highlights

• Jack’s retirement delayed on “24” (7 p.m., Fox).

• Hiro’s condition worsens on “Heroes” (8 p.m., NBC).

• Kaylie’s popularity surges on “Make it or Break It” (8 p.m., Family).

• A victim is found sawed in half on “CSI: Miami” (9 p.m., CBS).