Which is better than "Let's do it to them before they do it to us!" Mike Post's extended version of the "Hill Street Blues" theme: https://www.youtube.com/watch?v=fqH3qCxz2x0

"Let's be careful out there!" evolved into "Hey! Let's be careful out there!" "Hey! Hey! Let's be careful out there!" and I think the maximum expansion was "Hey! Hey! Hey! Hey! Let's be careful out there!" in season 4. I think the Hill Street theme was Mike Post's best.