When Alejandro Escovedo returns to the Castle Theatre Sunday night for his fourth show since 2010, he'll be bringing with him an exclusive, this-tour-only lineup — one likely never to be encountered on a stage in this configuration again.

Here's the who's who:

Chris Stamey: Man of many musical hats who produced AE's 2001 album, "A Man Under the Influence"; reunited with AE for the first time as new tour's music director/arranger/opening act (joined in the latter role by singer Millie McGuire); founded cult ’80s band The dB's; solo performer since 1983.

Mitch Easter: Played guitar on "A Man Under the Influence"; producer of R.E.M.'s early albums, through "Reckoning" (19 84); front man for ’80s rock band Let's Active (1981-90); producer/touring guitarist for Velvet Crush (mid-’90s).

Eric Heywood: Noted pedal steel and electric guitarist; most famously played/toured/and or recorded with the Pretenders and Son Volt; also, The Jayhawks, Tift Merritt, Jay Farrar, John Doe and Joe Henry.

Hector Munoz: Long-time AE drummer, dating all the way back to AE's classic True Believers era (1982-87); like Easter, also one of the original playres on "A Man Under the Influence" in 2001.

Mike Luzecky: The newest addition to the AE lineup for the current tour, on bass.