11 oddly glum, expressionless, exhausted and close to exit (5)

I haven't cracked this one yet — but the brilliant team at Fifteensquared have:

Odd-numbered letters of G [l] U [m] + E [x[ressionles] S (exhausted = emptied out) + end letter (close) of [exi] T . Reference to 11d PLUS ONE, as in a formal invitation to “Sam Bloggs and guest” which entitles you to bring a partner or friend.