The most common and most likely answer to this crossword clue is the 10 letter word STRATAGEMS
I've seen this crossword clue in Independent
S
T
R
A
T
A
G
E
M
S
More clues leading to the result STRATAGEMS
Buddy explains!

The straight part
We know that "plots" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case plots = stratagems.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does STRATAGEMS mean?
STRATAGEMS noun- A tactic or artifice designed to gain the upper hand, especially one involving underhanded dealings or deception.