Conversation so far:
What happened in 1961 with Tippi Hedren?
On October 13, 1961, Tippi Hedren received a call from an agent who told her a producer was interested in working with her.
Who called Tippi Hedren in 1961?
An agent from a producer.
Then what happened with Tipi Hedren after the call?
When the agent told Tippi Hedren the producer was Alfred Hitchcock, she agreed to sign a seven-year contract.
What movies did Tippi Hedren and Alfred Hitchcock make together?
The Birds(1963) and Marnie(1964).
What else di Tippi Hedren do with Alfred Hitchcock?
Alfred Hitchcock put Tippi Hedren through an extensive color screen test that lasted two days and cost $25,000, doing scenes from his previous films.

Question: What was the previous films?
Self-contained rewrite: What were the previous films that Alfred Hitchcock put Hedren through for a screen test?