have a tiger by the tail —(also: catch a tiger by the tail) engage in an undertaking which may prove extremely dangerous or difficult:
- Everybody seems to have their own opinion on how the concert will go: they have a tiger by the tail and are not sure themselves how to handle the huge crowd of fun seekers.
hold an eel by the tail —(also: catch an eel by the tail) attempt to control an elusive person or situation:
- He imagined I was in his power at Augsburg; he thought he had me; but he was holding an eel by the tail.
Note: Neither expression correlates in meaning with the phrase have the world by the tail—enjoy success and happiness:
- After all, the guy had the world by the tail —first class travel and first class hotels, money, glamour, beautiful women…