An evening for two guests: a companion for couples, chosen by both

Before anything else, Octavia confirms that the evening is a decision the two of you have made together. An arrangement intended as a surprise for a partner is declined, however kindly it is meant. Where both of you agree, everything that follows is simple: one of you sends the first message, and Octavia keeps every detail in that single conversation.

On the night, the same principle holds. Either of you may end the evening at any moment, without a reason and without discussion.

Dinner, most often. Wiltons for a formal evening, The Wolseley for a livelier one, or a hotel dining room you already know. An evening opening at the White Cube in Mason's Yard, or a late night at the Royal Academy. A walk down Pall Mall towards the palace as the light goes, followed by a martini at Dukes. A play on the Haymarket and a late supper afterwards. The shape is entirely yours; your companion is there to make it easier to enjoy.

Anniversaries and birthdays suit this arrangement especially well. A table at The Ritz, where the dining room still asks for a jacket and tie; a bottle chosen with some care; a companion who raises a glass to the two of you and means it. Tell Octavia the occasion, and she arrives knowing whose evening it is.

For a couple new to London, your companion is partly a guide. She knows which gallery has an opening this week, which bar keeps a corner quiet on a Friday, and how far it really is from The Ritz to the river, which is further than it looks on the map.

The notebook has two pieces worth reading beforehand: old world manners for the table, and the small palaces of St James's for where to stay close by.

A couples evening asks for a companion who is socially fluent and can hold two conversations without letting either drop. Thea is relaxed, on time, and especially good with visitors seeing London for the first time. Lea, spontaneous and fond of new plays, is one of the auburn and red haired companions, and she will have a view on the production by the interval. Bianka is soft-spoken and chooses tables well. Vanessa is curious and very easy to talk to, which helps when two people are both a little nervous.

Couples evenings are accepted only by companions who enjoy them, and Octavia asks each one before proposing her name. Nobody on the list is expected to take an arrangement she would rather not, which is one reason these evenings tend to go well: the person at your table chose to be there.

For a first evening, Octavia usually suggests two hours at £1,100: long enough for a drink at your hotel and one course somewhere near, short enough to decide afterwards whether you would like more. The four-hour dinner line at £1,800 suits a couple who already know the evening they want. The ladder is unchanged because there are two of you, since the fee is for her time. The rates page lists every line.

Couples visiting London often stay at The Ritz or Brown's, and residents may prefer their own house. Either suits. Hotels around Green Park and along Piccadilly are within a few minutes' walk of everything above, and the address is confirmed once, in writing, as for any booking. Booking explains the exchange from the first line to her arrival.