From Lady Gaga To Ivanka Trump, The Celebrity Gossip Girl Cameos Time Forgot

Alexa popped up in the final season of Gossip Girl, playing herself in a cameo set at a fashion show. Following a tiny catwalk disaster, Blair tries to save the day be sending Alexa out next. Alexa's response? 'There's no way in hell I'm going out there!' A lockdown queen ahead of her time.

So, Rachel was best known for playing Summer in The OC, and dated her co-star Adam Brody in real life. She then featured in the Gossip Girl finale as herself, in a scene where Kristen Bell – also playing herself – helps her prepare for an audition to play Blair. Blair was played by Leighton Meester, who is now married to Adam Brody. Keeping up? What a tangled web.

The actress and swimwear designer had a particularly fun arc in season 5, playing LA businesswoman Diana Henry, a pernicious gossip hound and love interest to Nate.

It is pretty indicative of how big Gossip Girl was that it could recruit Lady Gaga to perform in season 3 at the height of her incredibly successful Fame Monster period. She sung Bad Romance as part of a performance art piece watched by Blair et al. But Gaga wasn't the only singer to take the stage for Gossip Girl. Robyn, Gwen Stefani, DeadMau5 and Florence and the Machine also performed within the series.

Hilary had one of the more substantial roles on the celebrity spectrum. The Lizzie McGuire actress and chart-topping singer played famous actress Olivia Burke, a love interest of Dan's in season 3. She departed when she realised he had feelings for his friend Vanessa. Not that that lasted either. He only really ever had eyes for Serena.

Look, the series finale was a bit of a blur to us as we awaited what turned out to be a disappointing reveal of the identity of Gossip Girl. So distracted were we that we barely noticed that Lisa Loeb (who had popped up as herself in one previous episode) was back again, clearly dating Dan's dad Rufus. The singer, best known for her number 1 hit Stay, says it all came about through a friend who worked on the programme.

Now, she's the daughter of the President of the United States. Then, she was merely the daughter of the host of a reality television show. Weird, how the world can change, right? Ivanka appeared with her husband Jared Kushner in season four, where they met Serena's mum Lily and Dan's dad Rufus at a party. Coincidentally, Jared's future sister-in-law Karlie Kloss also popped up.

Like Hilary, ANTM queen played an actress. Named Ursula, she didn't get off to a very good start (she was something of a diva and did not treat Serena very nicely when she was hired as her assistant) but they soon became friends.

Blair single-handedly made the headband happen. We thought they were off limits post-primary school, but then we saw Queen B command her troops from the steps of the Constance rocking a headband and we re-evaluated everything. If you watched Gossip Girl as a teen, you definitely wanted to copy this look.

Hosiery was a wardrobe staple in Blair's world. Her love for tights knew no bounds, and she nailed the preppy look again and again.

Blair couldn't get enough of lime, lemon and orange. Who know zesty shades so could look so good?