What Happened to Sunday? (S04E15)

S04E01 A Home of Your Own S04E01 A Ticket to the Eclipse S04E02 The Royal Connection S04E02 One for the Lady S04E03 Time Out of Mind S04E03 Words and Music S04E04 Figures in a Landscape S04E04 No Flame Like An Old Flame S04E05 The Mouse That Died S04E05 Love's Neighbours' Lost S04E06 The Lost Art of Dying S04E06 Come Fly with Me! S04E07 The Other Game in Town S04E08 The World Between S04E09 Sunburst S04E10 To Cage a Sea Gull S04E11 Bang, Bang, You're Dead S04E12 Deja Vu S04E13 Duet For Three S04E14 Round Trip to Nowhere S04E15 What Happened to Sunday? S04E16 The Judas Touch S04E17 With Intent to Kill S04E18 The Crime That Wasn't S04E19 A Gathering of Ghosts S04E20 A Day Filled with Shadows S04E21 Voice in the Dark S04E22 The Color of Murder S04E23 Shadow Play S04E24 Overkill