  Multi-site and multi-year differential photometry of the triple star DG Leo
reveals a complex frequency spectrum that can be modelled as the combination of
at least three Delta Scuti type frequencies in the range 11.5-13 c/d (with
semi-amplitudes of 2-7 mmag) and a superimposed slow variability of larger
amplitude. The period of the slow variation fits very well with half the
orbital period of the inner spectroscopic binary indicating the presence of
ellipsoidal variations caused by the tidally deformed components in a close
configuration. These findings, together with the results of a recent
spectroscopic analysis (showing that the system consists of a pair of mild Am
stars and one A-type component of normal solar composition), infer that DG Leo
is an extremely interesting asteroseismic target. Identification of which
component(s) of this multiple system is (or are) pulsating and determination of
the excited pulsation modes will both contribute to a much better understanding
of the non-trivial link between multiplicity, chemical composition, rotation,
and pulsation in the lower part of the classical Cepheid instability strip.
