under lock and key

Meaning

1. (keep sth / put sth / be) under lock and key

   locked up safely somewhere; in prison

   We keep our valuables under lock and key.

In the movies · 1

• I always keep my important documents under lock and key because one can never be too sure.A Shot in the Dark1964
• Gentlemen, this must be kept under lock and key...Treasure Planet2002
• Pembroke! Get those documents under lock and key.Robin Hood2018
• My office, where it will remain under lock and key.Happy Death Day 2U2019

Learn it in full scenes

• A Shot in the Dark1964
  • Clouseau Investigates the Pistol Pen
  • Clouseau Interrogates Maria
  • Dreyfus Takes Over the Case

From the same entry

• lock horns
• lock away
• lock away
• lock in
• lock onto
• lock out
• lock out
• lock up
• lock up
• lock up
• lock, stock and barrel
• pick a lock