fall into a trap
To be fooled or deceived. I really worry that he's fallen into a trap by joining that disreputable company.
fall into a trap
1. Lit. to get caught in a trap. The tiger fell into a trap and leapt out again immediately. The boys tried to get a squirrel to fall into a trap, but squirrels are too clever.
2. and fall into the trap; fall into someone's trap Fig. to become caught in someone's scheme; to be deceived into doing or thinking something. We fell into a trap by asking for an explanation. I fell into his trap when I agreed to drive him home.