The capabilities of the considered space mission THESEUS for investigation of cataclysmic variables
(CVs) are discussed.Transient High-Energy Sky and Early Universe Surveyor (THESEUS)
is a space mission proposal accepted by the European Space Agency for a phase A study that
would study gamma-ray bursts and X-rays for investigating the early universe and for the multimessenger
astrophysics. It involves a Lobster-Eye X-ray telescope as well. The THESEUS and
SMILE international consortia involve the Czech Technical University in Prague and the Czech
teams are expected to contribute to the project, mainly to the X-ray telescope and related science
and software.