  We continue the study of heterotic non-Abelian BPS-saturated flux tubes
(strings). Previously, such solutions were obtained in U(N) gauge theories: N=2
supersymmetric QCD deformed by superpotential terms \mu A^2 breaking N=2
supersymmetry down to N=1. In these models one cannot consider the limit
\mu\to\infty which would eliminate adjoint fields: the bulk theory develops a
Higgs branch; the emergence of massless particles in the bulk precludes one
from taking the limit \mu\to\infty. This drawback is absent in the M model
(hep-th/0701040) where the matter sector includes additional "meson" fields M
introduced in a special way. We generalize our previous results to the M model,
derive the heterotic string (the string world-sheet theory is a heterotic
N=(2,0) sigma model, with the CP(N-1) target space for bosonic fields and an
extra right-handed fermion coupled to the fermion fields of the N=(2,2) CP(N-1)
model), and then explicitly obtain all relevant zero modes. This allows us to
relate parameters of the microscopic M model to those of the world-sheet
theory. The limit \mu\to\infty is perfectly smooth. Thus, the full-blown and
fully analyzed heterotic string emerges, for the first time, in the N=1 theory
with no adjoint fields. The fate of the confined monopoles is discussed.
