like lambs to the slaughter
like a lamb to (the) slaughter
Without concern for what is to come (because one does not foresee the trouble ahead). This phrase comes from the Bible. When I did business with Michael, I was like a lamb to the slaughter—I had no idea he was such a criminal mastermind. The poor kid and his defense team weren't aware of what the prosecution had in store—it was like lambs to slaughter the moment the trial began.
like lambs to the slaughterand like a lamb to the slaughter
Fig. quietly and without seeming to realize the likely difficulties or dangers of a situation. Young men fighting in World War I simply went like lambs to the slaughter. Our team went on the football field like lambs to the slaughter to meet the league-leaders.