He's 'deadly' [='dead'] serious about finding another job.
Officers are allowed to use 'deadly force' if necessary.
The two gang leaders are 'deadly' enemies.
(..) Griphook! Well done, Hermione. Oh no, you two're like you again. The Thief's Downfall, washes away all enchantments. Can be deadly. You don't say. Just out of interest, is there any other way out of here? No. What the devil are all (..)2011 Harry Potter and the Deathly Hallows: Part 2