Christmas 2015: best TV on today, Wednesday 23rd December

This two-part documentary shows David Suchet's fascination with St Paul after reading his letter to the Romans years ago. First shown in 2012, Suchet is visibly engaged by a grotto above Ephesus lined with early Christian frescos, his favourite seeming to be a painting of his hero, St Paul.

Snow Chick: a Penguin's Tale, 8:30pm, BBC1

Everyone loves penguins, it's hard not to. This hour-long documentary voiced by Kate Winslet shows an emperor penguin family, with the dads guarding the penguin eggs and the mums heading out to sea to stock up on food supplies. The baby penguin chick featured is the runt of the pack, born late and smaller than the rest of the others. You will not be able to resist this, we guarantee.

Prey, 9:00pm, ITV

The series reaches its conclusion tonight, with Detective Sergeant Susan Reinhardt (Rosie Cavaliero) managing to lose a prisoner shortly after capturing him. She also continues her hunt for prison officer David (Philip Glenister) and escapee prisoner Jules (MyAnna Buring) as well as dealing with her annoying boyfriend and sceptical boss who encourage her to take a break from the case.

Boomers, 9:30pm, BBC1

This sitcom featuring Alison Steadman and Philip Jackson gets a Christmas Special with the three 60-something couples in Calais, returning from a trip to a Christmas market. Some grumpy asides about gingerbread, Germans and Santa toys provide laughs, but Alan (Jackson) struggling to operate a voice recognition phone line is the funniest.

Christmas Shopping Fever: John Lewis and the Retail Race, 9:30pm, BBC2

Cherry Healey leads this documentary about the run up to Christmas in one of the country's biggest department stores. A large part of John Lewis's annual profits are made between Black Friday and Christmas, with households on average spending £800 in the six weeks leading up to Christmas. Watch how they attempt to lure customers away from online shopping and back into the shop through a bit of "retail theatre" – and, of course, that iconic Christmas advert.

Detectorists, 10:00pm, BBC4

Rejoin the members of the Danebury Metal Detecting Club where the wintry fields are looking very bare for Lance (Toby Jones) who isn't finding the usual ring-pulls. Can he locate any more gold? Series creator Mackenzie Crook has already teased the winter episode: "We got to bring the story to London for some extra-special scenes." Look out for those!

Toast of London, 10:00pm, Channel 4

This final episode in the series features a multitude of guest stars all saying what they really think of Toast (it's not good). The man himself gets a job working at The Globe in a production of Twelfth Night, entirely performed by dogs as "a metaphor for what's happening in Syria." No, we don't get it either. Look out for cameos from Martin Freeman, Jude Law and Sheila Hancock, amongst others.