Van attended Calvert Grammar School in Newport. After school he had odd jobs such as delivering groceries, shoveling snow, mowing lawns, and taking magazine subscriptions. Studing singing, dancing and the violin, Van set his sights on the stage after an annual show presented by his teachers. He sang and danced on stage wearing a straw hat and carrying a cane. Van wrote and starred in plays he and his friends performed in every unused barn in the area. He experienced his first bit of discouragement when he failed to make the drama club at Rogers High School, so he turned his interest into playing the violin in the orchestra and to playing basketball and baseball. He continued his interest in the stage outside of school at the Kiwanis and Lions clubs and attended shows at Newport's Casino Theater.
Van graduated High School in June of 1935 and his father urged him to attend Brown University to study law but Van was uninterested in law and tried unsucessfully to find a job sing or dancing that summer and instead spent the time frying clams at a roadside restaurant. The manager of the the restaurant encouraged Van to go to Broadway. He left for Broadway that September confident that he would succeed quickly.
Life was very hard during his first few months in New York and his confidence began to waver as he was turned down by agent after agent until December when he won a part by exaggerating his experience. It was called "Entre Nous" and only lasted four weeks at the Cherry Lane Theater in Greenwich Village. When his money got low he accepted a job as a substute dancer with a group touring New England. He left that job after a short time.
In May of 1936 he got is first part on Broadway by chance when watching a rehearsal of a new show "New Faces" with a friend and cast member. He was mistaken by the director as one of the performers and told to get on stage. Seizing the moment, he knocked himself out and got a part in the show which lasted 40 weeks and was paid $40 a week.
When the show closed in early 1937, he became a chorus boy at the Roxy Theater. Shortly after that he went on tour for several months as the third member of the comic team of Buster West and his wife Lucille Page.
He gained experience with his talents by entertaining at hotel resorts during the summer of 1938. In early 1939 he got his first job in a night club as one of "Eight Young Men of Manhattan" an act centering around Mary Martin at the stylish Rainbow Room. In 1940 he was back on the stage as the understudy for the three male leads, which included Desi Arnez, in George Abbott's "Too Many Girls". In December of 1940 he was cast in Abbott's production of"Pal Joey". Van had a dance number and a few lines. While "Pal Joey" was still running, Columbia Pictures invited him to Hollywood. He was not offered a contract and returned to New York where he resumed his part.
In early 1942 Warner Brothers offered him a 6 month contract at $300 a week. He immediately returned to Hollywood. Five and a half months into his contract he was given the lead in "Murder in the Big House". After shooting this "B" movie, the studio dropped his option. He decided to return to New York, but on his last night in Hollywood, while having dinner with Lucille Ball, he was introduced to Bill Grady, an MGM talent scout. Lucy convinced Grady to give Van a chance, and he told Van to report to the studio the next morning. He was given make-up tests, voice tests, and dramatic coaching for a short called "Crime Doesn't Pay". MGM signed him to a contract. He got a bit part in the Clark Gable and Lana Turner film "Somewhere I'll Find You". He was given a leading role in Dr. Gillespie's New Assistant" which started a series of films.
In 1943 he began to work steadily in Hollywood.