The 26-year-old singer has recently become pals with the 'Stay With Me' hitmaker and revealed they intend to sit down and write a song for the two of them to perform in the near future as they are both working on their second LPs.
She exclusively told BANG Showbiz: ''Sam Smith and I have developed a really nice friendship and I just feel kindred - like I just feel very similar to him, so we text occasionally and we've been out for cocktails and stuff. He's a wonderful person.
''Sam and I have talked at length about writing something vulnerable and something powerful, so I hope it will happen. I hope it's on the next of either of our albums.
''I have so much respect for him and I think we have similar intentions for our music too. I'm just so proud of him, out there killing it.''
But Mary - who shot to fame when she featured on Macklemore and Ryan Lewis' gay rights anthem 'Same Love' in 2012 - says she has far grander plans than just music, having recently released her debut album 'Heart On My Sleeve'.
She explained: ''I have so, so many plans. I just wish that the year was longer and I wish I had more time. I have screenplays in my head, I wanna write a musical, I wanna do Broadway, I'm working on my second book of poetry which also has essays in it, I wanna do a clothing line. There's so many things that I want to tackle, that I really believe are feasible that I would love to do, like movies.''
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