A client wants this font as the theme of a flyer. I've seen this font on a site recently and can't remember the name for the life of me, and it's surprisingly not in the Font Book on my computer. Googling "what is that font that's similar to Futura Medium with underlined superscript" has not been going well. 

That’s not “underlined superscript”, but the numero sign ☞ №.

Thank you for the reply. By definition, isn't that still underlined superscript? 

"Typographically, the numero sign combines the upper-case Latin letter N with a usually superscript lower-case letter o, sometimes underlined, resembling the masculine ordinal indicator." 

Yes. I was trying to say that in order to replicate that image, you wouldn’t look for fonts with support for underlined superscript glyphs, but you would check which fonts have a character in the Unicode slot U+2116 NUMERO SIGN. There are Futura versions which have this, but it might also be a different typeface. Hard to say from just these 2 letters. 

Oh okay! I see what you're saying. Thank you for the info! I was able to find it thanks to your help. I was right that it was similar to Futura, as it's Futura PT Medium. I feel like an idiot, but I'm also very relieved. Thanks again!

The numero in your sample may be constructed—it doesn’t quite match the one I found in Futura PT—the underline seems a bit closer to the 0 in your sample. I prefer the glyph over your sample, however.

I was thinking the same thing. Futura PT worked great though and was pretty close. The client was thrilled with the finished product, even if I wasn't. But I just don't like doing projects in which I don't have a lot of creative control.