In 1949, shortly after graduating from the Tartu School of Music, Seep joined the
Vanemuine theatre as an opera and operetta singer, opera soloist, and stage actress. Seep's first role at the Vanemuine was as Adele, Rosalinde's maid in
Johann Strauss II's 1874 operetta
Die Fledermaus in 1949. This was followed by a 1950 performance as Susanna, the countess's maid in
Mozart's 1786
opera buffa The Marriage of Figaro. Seep's career onstage at the Vanemuine would span over thirty years. Some of her more notable roles include: • Musette,
Giacomo Puccini's
La bohème (1952) • Gilda,
Giuseppe Verdi's
Rigoletto (1953) • Teele,
Oskar Luts'
Kevade (1953) • Margarethe,
Charles Gounod's
Faust (1953) • Violetta, Giuseppe Verdi's
La traviata (1954) • Vaike, Evald Aava's
Vikerlased (1955) • Norina,
Gaetano Donizetti's
Don Pasquale (1957) • Despina, Mozart's
Così fan tutte (1959) • Luisa,
Sergei Prokofiev's
Betrothal in a Monastery (1962) • Lola,
Pietro Mascagni's
Cavalleria rusticana (1963) • Lieschen,
Johann Sebastian Bach's
Coffee Cantata (1963) • Butterfly, Puccini's
Madame Butterfly (1966) • Matilde, Boris Kõrver's
Mees pisuhännaga (1968) • Violante, Mozart's
La finta giardiniera (1970) • Parasja, Yuri Milyutin's
Trembita (1973) • Guadalena,
Jacques Offenbach's
La Périchole (1974) • Mesihuul, Valdeko Viru's
Kuulsuse narrid (1976) • Grandmother,
Evgeny Schwartz's
The Snow Queen (1978) ==Film==