The 24-year-old actor and model was arrested, along with his girlfriend Uma von Wittkamp, on Wednesday after a routine traffic stop for failing to signal in Nebraska, according to multiple reports. A search of the 1992 Volvo turned up 14 grams of marijuana, 4 amphetamine pills, and 3 grams of psychedelic mushrooms, Page Six and TMZ confirmed. Hopper was booked on charges of possession of a controlled substance (psilocybin, which is in the mushrooms) and possession of marijuana (one ounce or less). Von Wittkamp, with whom Hopper has been stepping out publicly since 2015, was booked for two counts of...