The answers to the clues below will have something in common.

1. Futile effort
2. Activity with a list
3. Televised car chase, usually
4. Police action in a neighborhood, perhaps
5. Finding one's "Holy Grail"

Answers:

1. Wild goose chase
2. Scavenger hunt
3. Police pursuit
4. House-to-house search
5. Life-long quest

Credit:
NY Times Crossword
June 8, 2005
Richard Chisholm (#1-3 - adapted)