The unclued lights (two single words, one a proper noun, four pairs and one trio) share a certain feature.

Across

4 Insightful patient, ever worried (11)

11 Report of joints at hideout in London suburb (7)

12 Instruction to massage deep’s not hard (6)

16 Fears one is concealing crime (5)

19 Escape from hospital, heading off to shelter (7)

23 Alien resident in El Salvador producing ipecac and suchlike (7)

25 Goes easy on the French in tears (7)

30 I came from Rome, my lad, for game (7)

32 Effective contact with cricketer Plunkett (not married) and...