A hook play adds a single letter to the front or end of a word already on the board, creating a new word. It's one of the most efficient plays in Scrabble because it scores on the hook letter's row or column and the extended word simultaneously.
Front hooks vs. back hooks
Back hooks are more common — adding S, D, R, or N to existing words. Front hooks require more memorisation but are harder for opponents to anticipate. Classic front hooks: A+LIVE = ALIVE, RE+MOVE = REMOVE, UN+LOCK = UNLOCK.
High-value hook opportunities
Words ending in E are particularly hookable: GROVE → GROVES, SCAPE → SCAPES, BLAZE → BLAZED or BLAZER. Keep a mental list of common words on the board and which letters legally extend them.
Memory trick: The most reliable back hooks are S, D, R, and N. Front hooks: A, BE, DE, RE, UN, OUT, OVER. When in doubt, the unscrambler can show you all valid hook words from your current tiles.
Hooks that surprise opponents
Some hooks are deeply counterintuitive. BEAST → YEAST (front hook Y). HALE → SHALE (front hook S). ROVE → DROVE → GROVE is a chain. When you challenge a hook, be sure it's actually invalid — penalties add up fast.