She's giving birth in a matter of months but that hasn't stopped the Duchess of Sussex from carrying out her royal duties.
Wearing a black Givenchy coat and pleated dress, Meghan had her hair pulled back in a bun for the visit.
Prince Harry and Meghan Markle are no strangers to the West End, having recently gone to see Hamilton, so maybe the Duchess of Sussex will reunite with her old school chum for a slice of pie and some sugar, butter, flour.
It was Meghan's first engagement as a patron of the theatre after the Queen passed the role onto her earlier this month. It was taken when the Duchess was an aspiring actress as a teenager, long before she landed her most famous role in the legal drama Suits. She then added the hashtag #TBT.
The warning came after Meghan closed her own auto door last September while attending the Oceania exhibit at the Royal Academy of Arts.
Meghan has a stage background having studied theatre and global relations at Northwestern University, Illinois, and volunteered at a performing arts after-school programme for youngsters from underprivileged school districts in Los Angeles.
"Meghan and I did musicals together as kids", she captioned the photo on social media.
Harry and Meghan were photographed during that theatre night in December 2016, the first time they had been pictured together as a couple.
She also met fans waiting outside the university, hoping to catch a glimpse of the Duchess.
What did you think of Meghan's new hair look?
At the National Theatre she met with some of the teams and apprentices working behind the scenes, and watched a performance by schoolchildren from Edith Neville Primary School in Camden.
Another said: "Goddess Meghan!".