Both of her parents looked at her expectantly across the dinner table. The three of them were wearing paper party hats at her father’s insistence. They had finished the main course and were now taking a breather before dessert.

‘Well?’ said her mother, an expectant smile lighting up her small wrinkled face.

Bailey scanned the slip of paper with her ash-grey eyes. She sighed and dutifully read what it said. ‘What do lions sing at Christmas?’

Her parents both frowned as they tried to think of the answer.

‘I give up,’ said her father, scratching his thinning grey hair.

‘So do I,’ said her mother.

‘Jungle Bells.’

Her parents laughed. Bailey didn’t. She crumpled the piece of paper and dropped it onto the table.

It was Christmas Day. It also happened to be her birthday. She had just turned thirty.

Her mother put on her half-moon reading glasses and squinted down at her own cracker joke. Her eyes widened.

‘Ooh, you’ll like this one, Bailey. It’s right up your street.’

Somehow Bailey doubted that but she didn’t say anything.

Her mother took a deep breath. ‘What happened to the man who stole an advent calendar?’

Bailey paused for thought. As was her habit when she was thinking, she fiddled with the lock of hair that she wore loose down the left side of her face to cover the thin white scar that ran from the top of her cheek down to the bottom of her jaw. The scar had been inflicted upon her during the course of her job, the grim handiwork of a vicious perpetrator who still haunted her nightmares.

She curled the hair around her fingers and let it uncurl.

‘He got twenty-five days,’ she said.

Her mother looked a little crestfallen. ‘You’ve heard it before!’

Bailey shook her head.

Thirty. It had come so suddenly. Weren’t you supposed to do something special on your thirtieth? She hadn’t really had the chance to give it much thought as she’d been too busy working. Her last police operation had come to a close only recently and she was still getting over it; she’d been undercover in a women’s prison and had come perilously close to never making it out of there alive.

Now, here she was, thirty, single, at her parents’ suburban pebble-dashed house in Bromley, reading crummy cracker jokes. Not one to normally feel sorry for herself, she was finding it hard to shake the feeling of existential despondency that had settled upon her all of a sudden.

She realised she should probably try and make the effort to meet up with some friends. That’d put an end to the navel-gazing. But it had been a while since she’d done so. Immersed in undercover work, she’d let a lot of her friendships fall by the wayside. Although in truth there wasn’t much she could do about that; on her last case, posing as a prison inmate, inviting her friends to drop by for a visit at Her Majesty’s Pleasure just wouldn’t have been a viable option, not least because she’d been pretending to be someone completely different to who she actually was.