Possible Clues:

• Impressionist returning under pressure to host series ultimately gets one in the can
• Kidnappee, e.g
• Captured soldier or sniper maltreated
• Hostage, for example
• Senior PR (anag) — one in detention
• Is detained by one of those in 19 down
• One's detained someone snooping around boy
• Hostage runs into Crippen famously dropping round
• Edmond Dantès, e.g., before becoming the Count of Monte Cristo
• One is incarcerated