In American English, scheme, especially as a verb but also as a noun, suggests a crafty or secret plan to attain a sinister end.

Swartt sheathed his sword, the beginnings of a crafty plan forming in his mind.

From crafty plan, to downfall, to wheeze, to calamity; all in a few minutes.

It indicated strong-arm tactics and probable murder as a necessary requisite to a smooth and crafty plan.

Colter probably had been at the bottom of this crafty plan.

He took her to the orchard and followed out his crafty plan of surprise perfectly.

Through some crafty plan, The Cobra would manage to meet King Zobell on his own ground, in the presence of his friends.

Now he is back with a crafty new plan to destroy a valuable, if imperfect, mechanism that has done much to reduce the political influence of powerful special interests.

For all your smugness and your crafty little plans, I'm not going!

Her crafty little plan backfired and she lost a lot of money.