VIDEO : Can Exes Really Be Friends? Just Look at Mandy Moore and Wilmer Valderrama

Instagram Not every breakup has a bitter end. Case in point: Mandy Moore and Wilmer Valderrama , who dated from 2000 to 2002. After hanging out at Universal Studios' Halloween Horror Nights last fall, the exes had a surprise run-in Wednesday on the Paramount Studios lot in L.A. Moore, 32, and Valderrama, 36, made sure to document their happy reunion on Instagram (and plug each other's TV shows, of course). Moore, who stars in the new NBC series This Is Us , premiering Sept.