plunge to (something)
To fall or plummet down to some lower level or degree at a high and often uncontrollable speed. The bus skidded on the ice and plunged to bottom of the ravine. The stock market plunged to its lowest level in over 50 years.
plunge to something
1. to fall or drop down to something. The temperature plunged to zero last night. The burning car plunged to the floor of the canyon.
2. to dive or fall to one's death. She walked straight to the edge of the cliff and plunged to her death. The burro slipped and plunged to an untimely end.