Tortuous

adjective
highly complex or intricate and occasionally devious; ; ; ; ; ; ; ; - Sir Walter Scott
“the Byzantine tax structure”
Similar: byzantine, convoluted, involved, knotty, tangled
adjective
marked by repeated turns and bends
“a tortuous road up the mountain”
Similar: twisting, twisty, winding, voluminous
adjective
not straightforward
“his tortuous reasoning”