1 Adam: We need a boat, our cameraman, and something to lure the monster to the surface of the loch.
2 Jamie: So, some chum to throw overboard?
3 Adam: Yeah, I guess if we toss a friend overboard that might do the trick.
4 Jamie: I meant chum - as in chopped up fish bits.
4 Adam: Oh. I suppose that could work too.

I was thinking of the scene in Jaws where Police Chief Brody is tossing chum over the side of the Orca in an attempt to attract the titular shark so they can catch it. If you've seen the film, you know what happens next - one of my absolute favourite 30 seconds of film. If you haven't... it's a classic! Go watch it!

Spoiler links: The scene is so good that IGN rated it #5 in their list of the Top 100 Greatest Movie Moments of all time, beating out the infamous shower scene from Psycho, Elliot and the kids taking to the sky in their flying bicycles in E.T., Rhett Butler's "Frankly my dear, I don't give a damn," Indiana Jones outrunning the giant rolling boulder, and the original chestburster scene from Alien. And if you can't be bothered watching one of the best films ever made, here's the relevant 30 seconds on YouTube.

I briefly thought about using the word "burley" instead of "chum", but a quick bit of research revealed that burley is the word used for chum in Australia and New Zealand (thus my familiarity with it), but apparently nowhere else. So I thought the Mytbbusters should probably use the word "chum".

Which then led me to the punchline.