Get your slimy, webbed phalanges off ma boots!
We played this for the first time the other day. Thought it was a decent game, once we understood most of what was going on.
One thing we were unable to determine, though, was whether or not an objective like "Doc/Marty/Any" could be completed with just two cards, if one of them was a Doc/Marty card. The example was ambiguous, using multi-character cards, but in a combination that would have required all three of them anyway.
It always requires three cards to complete an event. The character cards in question are "either/or" propositions, not "both/and."
In the rulebook example on page 4, the 1955 event requires George, Lorraine, and Marty. The player has Marty/Lorraine, Marty, and George/Lorraine cards played to 1955. Completing the event requires all three cards.