  During the last decades, numerous exotic states which cannot be explained by
the conventional quark model have been observed in experiment. Some of them can
be understood as two-body hadronic molecules, such as the famous $X(3872)$,
analogous to deuteron in nuclear physics. Along the same line, the existence of
the triton leaves an open question whether there is a bound state formed by
three hadrons. Since, for a given potential, a system with large reduced masses
is more easier to form a bound state, we study the $BBB^{\ast}$ system with the
one-pion exchange potential as an exploratory step by solving the three-body
Schr\"odinger Equation. We predict that a tri-meson molecular state for the
$BBB^{\ast}$ system is probably existent as long as the molecular states of its
two-body subsystem $BB^*$ exist.
