What a cute couple! Lizzy Caplan and Tom Riley hold hands as they make their red carpet debut at the Prague Opera Ball

Lizzy Caplan and boyfriend Tom Riley made their red carpet debut at the Prague Opera Ball in the Czech Republic over the weekend.

The low-key pair were first pictured together in September, but have largely kept their romance under wraps.

However they put on a cute public display of affection on Saturday as they made their first official appearance as a couple.

Cute couple alert: Lizzy Caplan and Tom Riley made their red carpet debut at the Prague Opera Ball on Saturday

Cute couple alert: Lizzy Caplan and Tom Riley made their red carpet debut at the Prague Opera Ball on Saturday

Lizzy, 33, and 34-year-old Tom were seen holding hands while posing for photographs, and inside the event Lizzy was pictured pulling Tom in for a hug.

It seems the Masters Of Sex actress had also planted some kisses on her other half, as he had red lipstick marks on his cheek.

Lizzy looked stunning for the occasion in a black lace Dolce And Gabbana gown with bodice top, high neckline and sheer sleeves.

The star, who got her start in Freaks And Geeks and famously appeared in Mean Girls, carried a miniature box clutch and showed off her deep red manicure. 

Low-key couple: The two actors have been pictured together since September, but have largely kept their romance under wraps

Low-key couple: The two actors have been pictured together since September, but have largely kept their romance under wraps

Stunning starlet: Lizzy looked gorgeous for the occasion in a black lace gown with bodice top, high neckline and sheer sleeves
Stunning starlet: Lizzy looked gorgeous for the occasion in a black lace gown with bodice top, high neckline and sheer sleeves

Stunning starlet: Lizzy looked gorgeous for the occasion in a black lace gown with bodice top, high neckline and sheer sleeves

Lizzy's brunette locks were perfectly coiffed and she finished off her glamorous look with lots of black eyeliner and scarlet lips.

Meanwhile Tom, who took the stage during the evening, looked suave in a three-piece grey suit - also by Dolce And Gabbana - with black bow tie and white shirt.

The Da Vinci's Demons actor referenced the latest Mission Impossible movie on his Instagram account after the event, as he shared a picture of himself and Lizzy with the caption: 'The Prague Opera was exciting but I expected more failed assassination attempts/Tom Cruise on a zip line.' 

Finishing touches: The 33-year-old Masters Of Sex star also wore scarlet lipstick and lots of black eyeliner

Finishing touches: The 33-year-old Masters Of Sex star also wore scarlet lipstick and lots of black eyeliner

All aboard the love boat: In October, Da Vinci's Demons star Tom posted an Instagram photo which appeared to show the couple holding hands and jumping off a boat in Capri together

All aboard the love boat: In October, Da Vinci's Demons star Tom posted an Instagram photo which appeared to show the couple holding hands and jumping off a boat in Capri together

Lizzy was spotted at Tom's side in September inside a Da Vinci's Demons event, and the following month he posted an Instagram photo which appeared to show the couple holding hands and jumping off a boat in Capri together.

Lizzy was previously in a relationship with Friends star Matthew Perry for six years before their split in 2012.

The famous couple were hardly ever pictured together and kept their romance firmly out of the spotlight.

A source told DailyMail.com after their break-up that they parted ways because Matthew, now 46, didn't want to get married, explaining: 'He wasn't ready to make the full commitment so they split.' 

Former flame: Lizzy was previously in a relationship with Friends star Matthew Perry for six years before their split in 2012, but they were hardly ever pictured together. Here they are seen in September 2011

Former flame: Lizzy was previously in a relationship with Friends star Matthew Perry for six years before their split in 2012, but they were hardly ever pictured together. Here they are seen in September 2011

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