To smell a rat means to suspect an act of betrayal, but in this context there is no mention of any suspicion
Context: If they start to not suspect any foul play, there's a danger that they'll go and do something without thinking.
Hypothesis: If they start to smell a rat, there's a danger that they 'll go and do something without thinking.

Given this context, is the hypothesis true (Yes/No/I don't know)?