  This paper concerns twisted signature invariants of knots and 3-manifolds. In
the fibered case, we reduce the computation of these invariants to the study of
the intersection form and monodromy on the twisted homology of the fiber
surface. Along the way, we use rings of power series to obtain new
interpretations of the twisted Milnor pairing introduced by Kirk and
Livingston. This allows us to relate these pairings to twisted Blanchfield
pairings. Finally, we study the resulting signature invariants, all of which
are twisted generalisations of the Levine-Tristram signature.
