Episode Six
Group members Ian Gillan and Roger Glover left in 1969 to join Deep Purple , while drummer Mick Underwood founded Quatermass and later collaborated with Gillan . 
<triplet> Ian Gillan <subj> Deep Purple <obj> member of <triplet> Roger Glover <subj> Deep Purple <obj> member of <triplet> Quatermass <subj> 1969 <obj> inception <subj> Mick Underwood <obj> has part