And their union is the underlying theme of the Ford collection.

But the underlying theme of their too brief time together was drugs.

Often, the issues are narrow, but the underlying theme is the same.

This has been an underlying theme of the last 18 months.

"But the underlying theme is often something more basic, like who's in control."

There's always an underlying theme, all thrown together at the last second.

The band says the underlying theme is "loss of control."

Yet the underlying theme of both these books couldn't be more simple or positive.

But the underlying theme was what happened here in 2000.