"we accomplished nothing, simply because of the large number of people involved"
"the problems involved"
"the involved muscles"
"I don't want to get involved"
"everyone involved in the bribery case has been identified"

"the difficulties in which the question is involved"
"brilliant leadership mired in details and confusion"

"the Byzantine tax structure"
"Byzantine methods for holding on to his chairmanship"
"convoluted legal language"
"convoluted reasoning"
"the plot was too involved"
"a knotty problem"
"got his way by labyrinthine maneuvering"
"Oh, what a tangled web we weave"
"tortuous legal procedures"
"tortuous negotiations lasting for months"

"a castle involved in mist"
"the difficulties in which the question is involved"