Janet Jackson Holds Hands with Maxwell During London Date Night

Janet Jackson and Maxwell might have a little "Sumthin' Sumthin'" going on ... 'cause they turned heads when they arrived hand-in-hand at the 1,500th performance of "Cabaret At The Kit Kat Club" Monday evening in London!

Check out the photos -- they're beaming as they arrive at the famed Playhouse Theatre to view the show ... and they're certainly not trying to hide their PDA.

Just look at Janet ... she's grinning ear to ear and fully confident as she steps out with Maxwell in a white wide-legged pantsuit and slicked back hair. The "Ascension (Don't Ever Wonder)" singer compliments her beautifully in a pinstriped suit and looks happy to be by her side.

The musicians have been spotted together countless times, but never looking so cozy -- perhaps, that's the way love goes, as Janet sings in her hit song!

TMZ reached out to their reps for comment ... so far, no word back.

Janet has been quiet about her love life over the years, even marrying businessman Wissam Al Mana in a secret ceremony in 2012. Their marriage ended in 2017, and Janet's brother Randy Jackson alleged it was abusive that same year.

The "All For You" hitmaker also dated Jermaine Dupri from 2002 to 2008 and was married to René Elizondo between 1991 and 2000. She eloped with her first husband, childhood friend James DeBarge, when she was just 18 years old. The marriage was annulled a year later.