Linked word squares

The following are clues to 18 six-letter words that must be filled into the following three linked word squares.

The clues are in no particular order, but just for fun, I tried to arrange them to tell a little story (which has no relevance to the puzzle's solution).

Overlapping portions of each square will obviously share the same letters.

• 



• Buyer and seller


• Acknowledge


• I


• Dissent


• Plagiarized


• Mocked


• Last


• Evil


• Plan


• Instructions



• Venerate


• Chamber


• Military instruments


• Deathly


• Word with fire or search


• Ball-drops


• Lands

Answer

The eighteen words are (in the same order as in the question):

PRINCE (the artist later known as) Symbol
DEALER Buyer and seller
CREDIT Acknowledge
IODINE (the chemical element whose symbol is) I
UNREST Dissent
STOLEN Plagiarized
TEASED Mocked
ENDURE Last
SINFUL Evil

AGENDA Plan
RECIPE Instructions
ESTEEM Venerate
GROTTO Chamber
BUGLES Military instruments
LETHAL Deathly
ENGINE Word with fire or search
ERRORS Ball-drops (in Baseball, I believe)
ESTATE Lands

This gives the following grid:

B U G L E S
U N R E S T
G R O T T O
L E T H A L
E S T A T E A S E D
S T O L E N G I N E
        A G E N D A
        S I N F U L

        E N D U R E C I P E
        D E A L E R R O R S
                C R E D I T
                I O D I N E
                P R I N C E
                E S T E E M