It is someone's big day - but the arrival of an unexpected guest ensures that things do not go smoothly. It is not long before the supposedly blissful event turns into a potential disaster.

Freddie and Stuart fall out, resulting in Stuart moving in with Ash while Violet moves in with Freddie. It is not long before the arrangement starts to drive the new flatmates up the wall, prompting Violet and Ash to come up with a plan to get things back to normal.

Finding themselves both single, Violet and Ash consider dating new people, Violet has already met someone on the internet, while Ash's ex Chloe returns. Freddie, meanwhile, feels under pressure from Stuart to land a new acting role.

The gang decides to join Ash and Jess at a ballroom dancing class. Nimble on his feet, Stuart quickly becomes teacher's pet, leaving Freddie in a huff, while Violet becomes a hit with the amorous teacher in other ways. After seeking Freddie's advice, Ash decides to take his relationship with Jess to the next level.

Feeling unfit, Freddie and Stuart join Ash at his gym, where a young fitness instructor persuades the pair to sign up for an expensive membership. With Freddie and Stuart spending so much time at the gym, Violet and Penelope discover how pleasant their flat can be without the bickering pair in it.

Violet panics when her wealthy sister Lillian - whom she has not seen in years - announces a visit. Worried that Lillian will discover the truth about her circumstances, Violet and friends set in motion an elaborate plan to save her from humiliation. Meanwhile, Ash is keen to introduce the group to his new girlfriend, Jess - but he is in for a surprise.