Dallas star Jesse dressed smart-casual in a black jumper and grey jeans, while Cara showed off her petite figure in tiny shorts and electric blue embellished heels, which she teamed with a plain white blouse and black blazer.
The former Desperate Housewives star sat on the front row and got chatting away to music producer Mark Ronson, as well as Sean Lennon, son of John Lennon and Yoko Ono.
There could be a budding friendship between Mark and Jesse too, as they both support the New York Knicks basketball team. It's no secret that Jesse and Cara share a love for basketball, so we reckon all three of them couldn't stop talking about their love for the sport.
Jesse tweeted: "Great meeting Sean Lennon & @iamMarkRonsin today. Two talented lads! And I see we have something in common, Mark...@nyknicks! CHEERS!"
Jesse and Cara, who have been together for five years, arrived in London last week (13 June) following a trip to Monte Carlo to promote the forthcoming series of Dallas.
Since staying in the capital, the loved-up couple have been making their presence known by gracing plenty of celebrity events. They stunned at the Affinity Real Estate Shooting Stars Benefit dinner last week, and spent the weekend at a golfing tournament for the same cause.
Then last night (16 June), they added another fashion event to their list as they partied at Jimmy Choo's 'London Collections: Men' opening night party. We wonder if they have any time for sightseeing?!