Hilarie Burton by Fred Norris/The CW Hilarie Burton by Fred Norris/The CW

But which Derek?

Hint: He's not crazy.

That's right - Ernest Waddell is returning to the CW's One Tree Hill this season, and for multiple episodes, sources tell TVGuide.com.

As best my resident Tree Hill historian, Robyn, can explain it, shortly after Peyton's momma, Ellie, passed on, she learned she had a half-brother out there, somewhere. Enter Psycho Derek (played by Matt Barr). That Derek, however, was just a poser/flim-flam man/all-out psycho.

Just as "Derek" got his comeuppance, Peyton's actual sibling surfaced, and he was a tough-as-nails Marine with a tender heart. After a four-episode run in 2006, Waddell's Derek was deployed to Iraq, but not until he could escort his sis to a basketball banquet honoring Nathan. - Matt Mitovich

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" Tree Hill Video Preview: Carrie Tells Dan Her Psycho Plan
" Daphne Zuniga Takes on Tree Hill's Vicious Victoria
" Use our Online Video Guide to find Tree Hill clips and full episodes