  We present a new construction of four dimensional $\mathcal N=3$ theories,
given by M5 branes wrapping a $T^2$ in an M-theory U-fold background. The
resulting setup generalizes the one used in the usual class $\mathcal S$
construction of four dimensional theories by using an extra discrete symmetry
on the M5 worldvolume. Together with the M-theory U-fold description of $(0,2)$
$E$-type six-dimensional SCFTs, this allows to construct new, exceptional,
$\mathcal N=3$ theories.
