Context

This line is spoken by Lieutenant Columbo, played by Peter Falk, in the TV show Columbo (1971-2003).

Would anyone want to watch a mystery that's already been solved?

That was the big question when Columbo first aired in the early 1970s. Every episode famously flipped the classic whodunit formula by showing the audience the entire murder before a detective ever showed up on the scene. By the time Columbo would bumble in, we already knew who the murderer was and how they did it. Case closed, right?

Not exactly. The joy of watching this show is seeing Lt. Columbo pretend to stumble and bumble his way through a case while covertly outsmarting the most arrogant murderers imaginable.

He usually starts out by talking. Columbo might prattle on about some unimportant details or ask meaningless questions. Anything to get the suspects gabbing. Then, once they let their guard down, he hits them with a final question as he gets ready to walk out of the room—"Oh, just one more thing…why would your wife have been out on the boat alone when she couldn't swim?" 

Boom.

These false exits became a sort of trademark for Columbo. He'd ask them all the time, as almost an after thought, but the audience would know that this was the info he really wanted all along. Any villain who heard this phrase had to know his days were totally numbered.

Where you've heard it

It's always best to sneak in a nice, unassuming "just one more thing," when you've got some major news to share. Act casual and then drop the bombshell. "So, Chandler and I went to the winery today. Oh, just one more thing—we're getting married!" It's a fun way to bury the lead. The one time you don't want to hear this phrase is when you think you've gotten away with murder. It could be a hint that your investigator is smarter than you think.

Additional Notable References

• When Peter Falk finished writing his autobiography, titling it Just One More Thing was probably a huge no-brainer.
• Our favorite Columbo fan podcast happens to be called Just One More Thing.
• Steve Jobs would often sneak a Columbo-esque "one more thing" into his presentations when he was really looking to wow a crowd.

Pretentious Factor

If you were to drop this quote at a dinner party, would you get an in-unison "awww" or would everyone roll their eyes and never invite you back? Here it is, on a scale of 1-10.

No one could ever accuse Lt. Columbo of being pretentious, so you're in no danger if you drop his signature line.