pull the rug out from under

pull the rug out from under  {v. phr.},  {informal}
To withdraw support unexpectedly from; to spoil the plans of.
Bill thought he would be elected, but his friends pulled the rug out from under him and voted for Vin.
We were planning a vacation, but the baby's illness pulled the rug out from under us.
Categories: friends {informal} {v. phr.}

'pull the rug out from under' on video