The Ghosts Christmas special contains a scene so utterly lovely that BBC One should show it every weeknight straight after the News at Ten. We could all watch it, have a little cry, then clean our teeth and go to bed, ready to wake up the next morning as better, happier people. It might be odd to hear Christmas carol ‘In the Bleak Midwinter’ in summer, but nobody would mind. There’s no wrong time to be knocked off your feet by a wave of joy. The scene shows Charlotte Ritchie’s Alison sitting alone at the piano on Christmas day, her wish for a family-sung carol drowned out in the mix of in-laws’ needs. She starts to sing, alone, and is surprised by another voice. Soon, it’s not just one, but a whole chorus – and not those of her in-laws, but the motley of comedy ghosts she inherited along with a manor house as the last survivor of her line. To the living, Alison looks as though she’s singing solo, but really, she’s deep in the bosom of a… really weird-looking family.  There’s always something rousing about choral voices, especially at Christmas, especially after a Baileys trifle and a bucket of wine, but that’s not what makes the scene so perfect. It’s perfect because of the note it strikes about companionship and fellow-feeling, a note held all the way through series three. Series three episode ‘Something to Share?’, written by Mat Baynton and Jim Howick, is Ghosts’ finest achievement so far. It’s a psychologically complex episode that visits scenes from the life of Lolly Adefope’s character Kitty – a sunshine-faced 18th century noblewoman whose cause of death is still tba (though having met her nasty sister, we could hazard a guess). Adefope is excellent in it, and carves out deep hollows of emotion beneath Kitty’s giggling, simpering façade.  The episode’s real genius though, is the conceit of having Kitty’s family played in flashback by the Ghosts cast – at least, to begin with. Kitty’s sunny outlook applies equally to the present and the past. She rewrites any cruelty she’s experienced and looks back with the rosiest of tinted glasses. She sees the horrid sister who bullies her as kind and adoring, the stern father who rages at her as benevolent and upstanding, so mentally casts them as compassionate, caring Alison (Ritchie) and the stern but loving and fatherly Captain (a WWII ghost played by Ben Willbond). Other cast members appear as servants and local figures.  As the scales start to fall from Kitty’s eyes, her family’s true faces appear in her memories. Her father was no Captain and her sister was certainly no Alison. Kitty had chosen to remember them that way because she loves Alison and the other ghosts like family. They’re who she wanted around her in life as well as in death.  No matter that they’re from different centuries and have entirely different understandings of the world, the ghosts’ kinship transcends their differences. A caveman, a 1990s politician, an Edwardian aristocrat, a WWII captain, a 16th century witch, a Regency poet, a headless Elizabethan, a 1980s scoutmaster, a debutante from the 1800s and a 21st century orphan can all learn from each other and find common ground. Around a piano, singing a carol, they can be family.  And that is the shining heart of Ghosts, the message underpinning its brilliant silliness: we have more in common than that which divides us. Without a hint of sappiness, that’s what catches unexpectedly in your throat mid-laugh.  Ghosts series 1-3 are available to stream on BBC iPlayer.