The article presents a new theoretical and research approach to the problem of man's ludic activity in adulthood. The theoretical thread presents the authoress' personal concept of quasi-mythical in nature ludic behaviour, substitutive in regards to participation in the archaic living myth. What lies at their base are the 'mythos' type cognitive processes proper to the mind of man, complementary to processes of the logos type, and the 'mythical' way connected to them in which man refers to the surrounding world. Characteristic elements of contemporary forms of 'mythos' have been distinguished in relation to its archaic forms. The empirical strain concerns chosen fragments of the authoress' own research on young adults' (aged from 19 to 32) experiences of participation in cultural phenomena that belong to the mythos domain. The study comprised 91 participants of historical re-enactment, 88 fantasy readers and 91 rave participants. An attempt to carry out a typology of participation in ludic 'mythos'-type realms has been made on the basis of the identified dimensions of experience common to the three sub-cultures studied. The theoretical model of contemporary quasi-mythical behaviour has also undergone empirical verification.