[No spoilers]

Last night, BBC1 saw the return of divorce law drama, The Split. The first episode of the second series saw action pick up three months after the end of the first, with Hannah Stern (played by Bafta-winning Nicola Walker) returning to family law practice in the aftermath of a leak which exposed the adultery of her own husband (the ever-fantastic Stephen Mangan).

The episode centres around a prominent, married, public figure named Fi Hansen, who consults Hannah for advice in respect of her pre-nuptial agreement. She asks whether this agreement can be changed, and refers to a term of the agreement requiring her to exercise a certain amount per week.

TV dramas are known for playing fast and loose with the truth, but how much does The Split’s account of pre-nups marry with the reality? Can they require your spouse to exercise a certain amount, and can they be varied once entered?

Pre-nups are agreements entered into by prospective spouses, which establish and regulate the way in which the couple hold their assets during the marriage, and how those assets should be divided in the event of divorce. Both parties should take legal advice, provide full financial disclosure, and there should be no undue influence.

Because a pre-nup is simply an agreement between two people, the document is entirely bespoke to the couple, it can be completely unique to them and their circumstances, and can include any term that they both agree. Whilst it is possible in principle that a pre-nup could include a term regulating how often one or both parties to the marriage should exercise, such a term would be strongly advised against by the legal term representing the spouse suggesting such a term, since proposing such a clause could scupper the whole agreement, or even the marriage itself.

In the episode, Hannah proposes a post-nuptial agreement to revise the pre-nup. Post-nuptial agreements are identical in most respects to pre-nups save that they are entered into during the course of the marriage, as opposed to in anticipation of it.

Just as theoretically a couple can agree any terms they like in a pre-nup, they can also agree to vary any of those terms at any point during the marriage. In fact, it is common to include a clause in the pre-nup confirming that the couple are able to review and revise the agreement at any point in the future by executing a new deed.

It can even be beneficial to revisit and re-agree the pre-nup during the marriage because pre- and post-nups are not legally binding. They only form one of the ‘circumstances’ that a judge must consider when deciding what is a fair division of matrimonial assets on divorce, and the weight that the judge will give to the consideration of the pre- or post-nup is likely to be greater where such an agreement was entered into nearer to the end of the marriage.

So, all in all, top marks to the script-writers of The Split for their account of pre- and post-nuptial agreements. That said, we would never advise that you take legal advice from TV dramas. Instead, book an appointment with one of our expert family lawyers.