in me·di·as res 
(ĭn mē′dē-əs rās)
(ĭn mē′dē-əs rās)adv.
In or into the middle of a sequence of events, as in a literary narrative.
[Latin in mediās rēs : in, into + mediās : accusative pl. feminine of medius, in the middle of + rēs, accusative pl. of rēs, thing.]