16d.   Small key locking in a painting (8)  *E*S*A**
17d.   First of cops on track for Bow Street ? (8)  *R*S*E**
27a.    Turn bridge partner makes you pass on  (2 , 4) *O/****
6d.  Even Mafia characters go off pastry served up here ?  (9)
        T***T*R*A    TRATTORIA ? but parsing ?